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BORROWINGS (Narrative) (Details) - USD ($) |  |  | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Feb. 01, 2019 | Aug. 23, 2012 | Jun. 30, 2019 | Dec. 31, 2016 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019 | Jan. 01, 2018
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |  |
Remaining available balance for the federal funds lines |  |  |  |  | $ 972,000,000.0 |  | $ 682,000,000.0 |
Maximum collateral dependent line of credit with the FHLB |  |  |  |  | 5,300,000,000 |  | 5,200,000,000 |
Subordinated debt |  |  |  | $ 150,000,000.0 | 158,500,000 |  |  |
Prepayment penalty |  | $ 19,600,000 |  |  |  |  |  |
Amortization expense included as a component of interest expense |  |  | $ 502,000 |  |  | $ 994,000 |  |
Remaining borrowing capacity |  |  |  |  | 25,000,000.0 |  | 25,000,000.0 |
Trust Preferred Capital Notes |  |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |  |
Trust preferred capital notes principal balance |  |  |  |  | 150,500,000 |  |  |
Remaining fair value discount on acquired notes |  |  |  |  | 14,500,000 |  |  |
Long-term debt borrowings |  |  |  |  | 155,159,000 |  |  |
Subordinated Debt |  |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |  |
Remaining fair value discount on acquired notes |  |  |  |  | $ 1,300,000 |  | $ 1,400,000 |
Stated percentage on debt instrument |  |  |  | 5.00% |  |  |  |
Debt maturity date |  |  |  | Dec. 15, 2021 | Dec. 15, 2026 |  |  |
Long-term debt borrowings |  |  |  |  | $ 158,500,000 |  |  |
PPPLF Advances |  |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |  |
Stated percentage on debt instrument |  |  |  |  | 0.35% |  |  |
Long-term debt borrowings |  |  |  |  | $ 189,941,000 |  |  |
Remaining borrowing capacity |  |  |  |  | $ 1,500,000,000 |  |  |
LIBOR | Subordinated Debt |  |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |  |
Three-month LIBOR rate plus |  |  |  |  | 3.175% |  |  |
StellarOne Bank and Xenith [Member] | Trust Preferred Capital Notes |  |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |  |
Trust preferred capital notes principal balance |  |  |  |  | $ 58,500,000 |  |  |
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 |  |  |  |  |  |  |  | $ 259,000
Stated percentage on debt instrument |  |  |  |  |  |  |  | 6.75%
Access National Bank |  |  |  |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |  |  |  |
Trust preferred capital notes principal balance | $ 5,000,000.0 |  |  |  |  |  |  |

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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