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Significant Accounting Policies - Impact of Topic 326 (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Jan. 01, 2020
--- | --- | ---
Allowance-debt securities available for sale |  |
Accrued interest receivable for debt securities available for sale debt | $ 6,800 |
Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | $ 16,833
Liabilities |  |
Reserve for off-balance-sheet credit exposures |  | 5,492
Post ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 70,581
Liabilities |  |
Reserve for off-balance-sheet credit exposures |  | 5,492
Pre-ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 53,748
Commercial Loans | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 715
Commercial Loans | Post ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 19,006
Commercial Loans | Pre-ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 18,291
Commercial Real Estate Loans | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 9,306
Commercial Real Estate Loans | Post ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 30,496
Commercial Real Estate Loans | Pre-ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 21,190
Real Estate Construction | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 2,954
Real Estate Construction | Post ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 6,158
Real Estate Construction | Pre-ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 3,204
Retail Real Estate | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 3,292
Retail Real Estate | Post ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 13,787
Retail Real Estate | Pre-ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 10,495
Retail Other | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 566
Retail Other | Post ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | 1,134
Retail Other | Pre-ASC 326 | Accounting Standards Update 2016-13 |  |
Assets |  |
Portfolio Loans, allowance for loan losses (in dollars) |  | $ 568

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- Definition Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with allowance for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82922866-210454 + Details
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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
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