Atlantic Union Bankshares Corporation Annual report pursuant to Section 13 and 15(d)

SECURITIES (Narrative) (Details)

v3.20.4

SECURITIES (Narrative) (Details)	12 Months Ended
SECURITIES (Narrative) (Details)	Dec. 31, 2020 USD ($) security	Dec. 31, 2019 USD ($) security
Schedule of Investments [Line Items]
Available for sale securities that had been in a continuous loss position for more than 12 months	$ 17,600,000	$ 75,000,000.0
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	101,000	696,000
AFS securities in an unrealized loss, credit related impairment	0	0
Available for sale securities, allowance for credit losses	0
HTM securities past due or non accrual	0
Available for sale securities past due or non-accrual	0
HTM securities, additional reserve for allowance for credit losses	0
Restricted equity securities consist of Federal Reserve Bank stock	67,000,000.0
Federal Home Loan Bank Stock	$ 27,800,000	$ 63,900,000
Available-for-sale Securities
Schedule of Investments [Line Items]
Available for sale securities that had been in a continuous loss position for more than 12 months, Number of issues \| security	15	47
Non-agency collateralized mortgage obligations
Schedule of Investments [Line Items]
SSFA rating percentage	20.00%

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Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of increase (decrease) in allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

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