Atlantic Union Bankshares Corporation Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)
Notes Tables
Notes Details

SECURITIES (Narrative) (Details)

v3.21.1

SECURITIES (Narrative) (Details)	3 Months Ended	12 Months Ended
SECURITIES (Narrative) (Details)	Mar. 31, 2021 USD ($) security	Dec. 31, 2020 USD ($) security
Schedule of Investments [Line Items]
Available for sale securities that had been in a continuous loss position for more than 12 months	$ 21,300,000	$ 17,600,000
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	93,000	101,000
AFS securities in an unrealized loss, credit related impairment	0	0
Available for sale securities past due or non-accrual	0	$ 0
Held to maturity securities, past due	$ 0
Federal Home Loan Bank requires Bank to maintain percentage of stock equal to outstanding borrowings	3.75%	4.25%
Percentage of Federal Reserve Bank of Richmond reserve	6.00%	6.00%
Restricted equity securities consist of Federal Reserve Bank stock	$ 67,000,000.0	$ 67,000,000.0
Federal Home Loan Bank Stock	$ 9,800,000	$ 27,800,000
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	12	15
Non-agency collateralized mortgage obligations
Schedule of Investments [Line Items]
SSFA rating percentage	20.00%

- Definition

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

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Debt Securities, Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions.

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- Definition

Federal home loan bank requires bank to maintain percentage of stock equal to outstanding borrowings.

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Required percentage of common stock investment percentage to outstanding capital.

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Simplified supervisory formula approach rating.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563

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- Definition

Amount of investment in debt security measured at amortized cost (held-to-maturity), past due.

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-Name Accounting Standards Codification
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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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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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