Annual report pursuant to Section 13 and 15(d)

FAIR VALUE MEASUREMENTS (Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details)

v3.10.0.1
FAIR VALUE MEASUREMENTS (Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($)
Dec. 31, 2018
Dec. 31, 2017
ASSETS    
Securities available for sale, at fair value $ 1,774,821,000 $ 974,222,000
Loans held for sale 0 40,662,000
Cash flow hedges   49,000
Fair value hedges 1,872,000 1,598,000
Best efforts forward delivery commitments   12,000
LIABILITIES    
Interest rate swap 19,426,000 1,350,000
Cash flow hedges 4,786,000 8,005,000
Fair value hedges 1,684,000 76,000
Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Securities available for sale, at fair value 0 0
Loans held for sale   0
Cash flow hedges   0
Fair value hedges 0 0
Best efforts forward delivery commitments   0
LIABILITIES    
Interest rate swap 0 0
Cash flow hedges 0 0
Fair value hedges 0 0
Significant Other Observable Inputs Level 2    
ASSETS    
Securities available for sale, at fair value 1,774,821,000 974,222,000
Loans held for sale   40,662,000
Cash flow hedges   49,000
Fair value hedges 1,872,000 1,598,000
Best efforts forward delivery commitments   0
LIABILITIES    
Interest rate swap 19,426,000 1,350,000
Cash flow hedges 4,786,000 8,005,000
Fair value hedges 1,684,000 76,000
Significant Unobservable Inputs Level 3    
ASSETS    
Securities available for sale, at fair value 0 0
Loans held for sale   0
Cash flow hedges   0
Fair value hedges 0 0
Best efforts forward delivery commitments   12,000
LIABILITIES    
Interest rate swap 0 0
Cash flow hedges 0 0
Fair value hedges 0 0
Recurring    
ASSETS    
Loans held for sale   40,662,000
Cash flow hedges   49,000
Fair value hedges 1,872,000 1,598,000
Best efforts forward delivery commitments   12,000
LIABILITIES    
Interest rate swap 19,426,000 1,350,000
Cash flow hedges 4,786,000 8,005,000
Fair value hedges 1,684,000 76,000
Recurring | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Loans held for sale   0
Cash flow hedges   0
Fair value hedges 0 0
Best efforts forward delivery commitments   0
LIABILITIES    
Interest rate swap 0 0
Cash flow hedges 0 0
Fair value hedges 0 0
Recurring | Significant Other Observable Inputs Level 2    
ASSETS    
Loans held for sale   40,662,000
Cash flow hedges   49,000
Fair value hedges 1,872,000 1,598,000
Best efforts forward delivery commitments   0
LIABILITIES    
Interest rate swap 19,426,000 1,350,000
Cash flow hedges 4,786,000 8,005,000
Fair value hedges 1,684,000 76,000
Recurring | Significant Unobservable Inputs Level 3    
ASSETS    
Loans held for sale   0
Cash flow hedges   0
Fair value hedges 0 0
Best efforts forward delivery commitments   12,000
LIABILITIES    
Interest rate swap 0 0
Cash flow hedges 0 0
Fair value hedges 0 0
Obligations of states and political subdivisions    
ASSETS    
Securities available for sale, at fair value 468,491,000 301,824,000
Obligations of states and political subdivisions | Recurring    
ASSETS    
Securities available for sale, at fair value 468,491,000 301,824,000
Obligations of states and political subdivisions | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Securities available for sale, at fair value 0 0
Obligations of states and political subdivisions | Recurring | Significant Other Observable Inputs Level 2    
ASSETS    
Securities available for sale, at fair value 468,491,000 301,824,000
Obligations of states and political subdivisions | Recurring | Significant Unobservable Inputs Level 3    
ASSETS    
Securities available for sale, at fair value 0 0
Corporate bonds    
ASSETS    
Securities available for sale, at fair value 167,696,000 113,880,000
Corporate bonds | Recurring    
ASSETS    
Securities available for sale, at fair value 167,696,000 113,880,000
Corporate bonds | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Securities available for sale, at fair value 0 0
Corporate bonds | Recurring | Significant Other Observable Inputs Level 2    
ASSETS    
Securities available for sale, at fair value 167,696,000 113,880,000
Corporate bonds | Recurring | Significant Unobservable Inputs Level 3    
ASSETS    
Securities available for sale, at fair value 0 0
Mortgage-backed securities    
ASSETS    
Securities available for sale, at fair value 1,129,865,000 548,858,000
Mortgage-backed securities | Recurring    
ASSETS    
Securities available for sale, at fair value 1,129,865,000 548,858,000
Mortgage-backed securities | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Securities available for sale, at fair value 0 0
Mortgage-backed securities | Recurring | Significant Other Observable Inputs Level 2    
ASSETS    
Securities available for sale, at fair value 1,129,865,000 548,858,000
Mortgage-backed securities | Recurring | Significant Unobservable Inputs Level 3    
ASSETS    
Securities available for sale, at fair value 0 0
Other securities    
ASSETS    
Securities available for sale, at fair value 8,769,000 9,660,000
Other securities | Recurring    
ASSETS    
Securities available for sale, at fair value 8,769,000 9,660,000
Other securities | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Securities available for sale, at fair value 0 0
Other securities | Recurring | Significant Other Observable Inputs Level 2    
ASSETS    
Securities available for sale, at fair value 8,769,000 9,660,000
Other securities | Recurring | Significant Unobservable Inputs Level 3    
ASSETS    
Securities available for sale, at fair value 0 0
Interest Rate Swap    
ASSETS    
Interest rate derivatives 19,426,000 1,350,000
Interest Rate Swap | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Interest rate derivatives 0 0
Interest Rate Swap | Significant Other Observable Inputs Level 2    
ASSETS    
Interest rate derivatives 19,426,000 1,350,000
Interest Rate Swap | Significant Unobservable Inputs Level 3    
ASSETS    
Interest rate derivatives 0 0
Interest Rate Swap | Recurring    
ASSETS    
Interest rate derivatives 19,426,000 1,350,000
Interest Rate Swap | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Interest rate derivatives 0 0
Interest Rate Swap | Recurring | Significant Other Observable Inputs Level 2    
ASSETS    
Interest rate derivatives 19,426,000 1,350,000
Interest Rate Swap | Recurring | Significant Unobservable Inputs Level 3    
ASSETS    
Interest rate derivatives $ 0 0
Interest Rate Lock Commitments    
ASSETS    
Interest rate derivatives   559,000
Interest Rate Lock Commitments | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Interest rate derivatives   0
Interest Rate Lock Commitments | Significant Other Observable Inputs Level 2    
ASSETS    
Interest rate derivatives   0
Interest Rate Lock Commitments | Significant Unobservable Inputs Level 3    
ASSETS    
Interest rate derivatives   559,000
Interest Rate Lock Commitments | Recurring    
ASSETS    
Interest rate derivatives   559,000
Interest Rate Lock Commitments | Recurring | Quoted Prices in Active Markets for Identical Assets Level 1    
ASSETS    
Interest rate derivatives   0
Interest Rate Lock Commitments | Recurring | Significant Other Observable Inputs Level 2    
ASSETS    
Interest rate derivatives   0
Interest Rate Lock Commitments | Recurring | Significant Unobservable Inputs Level 3    
ASSETS    
Interest rate derivatives   $ 559,000