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Derivatives and Hedging Activities Derivatives and Hedging Activities (Details Textual) - USD ($) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Interest rate swap derivative financial instruments |  |  |
Debt securities pledged as collateral | $ 1,333,455,000 | $ 1,447,808,000 |
Interest Rate Lock Commitments |  |  |
Interest rate swap derivative financial instruments |  |  |
Off-balance Sheet Commitments | 59,974,000 | 67,861,000 |
Interest Rate Swap One |  |  |
Interest rate swap derivative financial instruments |  |  |
Forecasted Notional Amount | 160,000,000 |  |
Interest Rate Swap Two |  |  |
Interest rate swap derivative financial instruments |  |  |
Forecasted Notional Amount | 100,000,000 |  |
Interest Rate Swaps |  |  |
Interest rate swap derivative financial instruments |  |  |
Interest rate expense recorded on interest rate swap | 8,013,000 | $ 8,013,000 | $ 8,035,000
Unrealized loss to be reclassified within twelve months | 1,663,000 |  |
Debt securities pledged as collateral | 4,730,000 |  |
Collateral pledged from counterparties to the Company | 0 |  |
Forward commitments to sell TBA securities |  |  |
Interest rate swap derivative financial instruments |  |  |
Forecasted Notional Amount | $ 40,750,000 |  |

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- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994 + Details
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- Definition The premium (cost) of a hedge, expensed during the period. + References No definition available. + Details
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- Definition Nominal or face amount used to calculate payments on the derivative liability. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959 + Details
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- Definition The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 10 -Section 05 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=109246787&loc=d3e93645-111703 + Details
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