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v3.19.3.a.u2

BORROWINGS (Narrative) (Details) - USD ($) |  |  |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Aug. 29, 2019 | Feb. 01, 2019 | Aug. 23, 2012 | Dec. 31, 2016 | Dec. 31, 2019 | Dec. 31, 2018 | Jan. 01, 2018
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Remaining available balance for the federal funds lines |  |  |  |  | $ 682,000,000.0 | $ 382,000,000.0 |
Remaining borrowing capacity with correspondent banks |  |  |  |  | 25,000,000.0 | 25,000,000.0 |
Maximum collateral dependent line of credit with the FHLB |  |  |  |  | 5,200,000,000 | 4,000,000,000.0 |
Subordinated debt |  |  |  | $ 150,000,000.0 | 158,500,000 | 158,500,000 |
Prepayment penalty |  |  | $ 19,600,000 |  |  |  |
Unamortized prepayment penalty recognized as a component of noninterest expense | $ 7,400,000 |  |  |  |  |  |
Trust Preferred Capital Notes |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Trust preferred capital notes principal balance |  |  |  |  | 150,500,000 |  |
Remaining fair value discount on acquired notes |  |  |  |  | 14,900,000 |  |
Subordinated Debt |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Remaining fair value discount on acquired notes |  |  |  |  | $ 1,400,000 | $ 1,600,000 |
Stated percentage on debt instrument |  |  |  | 5.00% |  |  |
Subordinated debt maturity date |  |  |  | Dec. 15, 2021 | Dec. 15, 2026 |  |
LIBOR | Subordinated Debt |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Three-month LIBOR rate plus |  |  |  |  | 3.175% |  |
Acquisitions, Prior To 2006 |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Trust preferred capital notes principal balance |  |  |  |  | $ 58,500,000 |  |
StellarOne Bank and Xenith [Member] | Trust Preferred Capital Notes |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Trust preferred securities acquired |  |  |  |  | 87,000,000.0 |  |
Xenith |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Subordinated debt |  |  |  |  |  |  | $ 8,500,000
Xenith | Subordinated Debt |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Remaining fair value discount on acquired notes |  |  |  |  | $ 51,000 |  | $ 259,000
Stated percentage on debt instrument |  |  |  |  |  |  | 6.75%
Access National Bank |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |
Trust preferred securities acquired |  | $ 5,000,000.0 |  |  |  |  |

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