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Derivative Instruments and Hedge Activities - Additional Information (Details) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Derivative [Line Items] |  |  |  |
Derivative notional amount |  | $ 341,358,000 | $ 548,969,000 |
Unrealized gain (loss) to be reclassified as an decrease to interest expense during the next twelve months |  | (85,000) |  |
Fair value of derivatives net liability position |  | 8,500,000 |  |
Collateral amount posted |  | 8,500,000 |  |
Settlement obligation termination value |  | 8,500,000 |  |
Interest Rate Swaps | Interest Expense |  |  |  |
Derivative [Line Items] |  |  |  |
Increase (decrease) in FHLB expense |  | (1,600,000) | (1,300,000) | $ 579,000
Other Interest Rate Derivatives |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative notional amount |  | $ 332,056,000 |  |
Derivative maturity date, start year |  | Apr. 30, 2020 |  |
Derivative maturity date, end year |  | Jan. 31, 2030 |  |
Derivative instruments transaction fees |  | $ 1,200,000 | 1,700,000 | $ 393,000
Other Credit Derivatives |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative notional amount |  | 9,300,000 | 4,400,000 |
Derivatives Designated as Hedging Instruments | Interest Rate Swaps | Cash Flow Hedges |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative notional amount |  | 0 | 250,000,000 |
Termination of designated as cash flow hedges to reduce interest risk | $ 250,000,000 |  |  |
Transaction, net of tax | $ 383,000 |  |  |
Remaining balance in accumulated other comprehensive income |  | $ 366,000 |  |
Federal Home Loan Bank Advances | Derivatives Designated as Hedging Instruments | Interest Rate Swaps | Cash Flow Hedges |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative notional amount |  |  | $ 250,000,000 |

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- Definition Derivative instruments transaction fees. + References No definition available. + Details
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- Definition Increase (decrease) in federal home loan bank expense. + References No definition available. + Details
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- Definition Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e681-108580 + Details
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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959 + Details
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- Definition The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959 + Details
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