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Federal Home Loan Bank and Federal Reserve Bank Borrowings (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
FHLB Fixed Rate Advances, Maturities Summary [Abstract] |  |  |
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate of Amounts Due within One Year of Balance Sheet Date | 2.64% |  |
Federal Home Loan Bank, Advances, Maturities Summary, Fixed Rate, under One Year | $ 392,000 |  |
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, One To Five Years From Balance Sheet Date | 3.85% |  |
FHLB Fixed Rate Advances, Over 1 through 5 years | $ 2,000 |  |
FHLB Fixed Rate Advances, Weighted Average Interest Rate, Due after 10 years | 5.37% |  |
FHLB Fixed Rate Advances, Due after 10 years | $ 5,000 |  |
FHLB Fixed Rate Advances, Total Amount before valuation adjustment | 399,000 |  |
Valuation adjustment from acquisition accounting | 523 |  |
FHLB Fixed Rate Advances, Total Amount | 399,523 |  |
Federal Home Loan Bank, Advances, Activity for Year [Abstract] |  |  |
FHLB Advances | 399,523 | $ 11,579 | $ 6,493
Federal Home Loan Bank, Advances, Activity for Year, Average Balance of Agreements Outstanding | 166,563 | 79,788 | 79,673
Maximum month-end balance during the year | $ 399,523 | $ 317,480 | $ 250,515
Weighted average rate during the year | 2.29% | 1.33% | 0.80%
Weighted average rate at December 31 | 2.68% | 4.08% | 5.42%
FHLB Borrowing Capacity | $ 1,620,000 | $ 1,430,000 |
Federal Reserve Bank, Advances, Activity for Year [Abstract] |  |  |
Average balance during the year | 14 |  |
Federal Reserve Bank borrowing capacity | $ 107,100 | $ 100,100 |

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- Definition Federal Home Loan Bank, Advances, Maturities Summary, Weighted Average Interest Rate, One To Five Years From Balance Sheet Date + References No definition available. + Details
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- Definition Federal Home Loan Bank, Advances, Maturities Summary by Interest Rate Type, Fixed Rate, after Ten Years + References No definition available. + Details
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- Definition Federal Home Loan Bank, Advances, Maturities Summary by Interest Rate Type, Fixed Rate, Before Valuation Adjustment + References No definition available. + Details
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- Definition Federal Home Loan Bank, Fixed Rate Advances, Valuation Adjustment From Acquisition Accounting + References No definition available. + Details
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- Definition Federal Reserve Bank, Advances, Activity for the year, average balance of agreements outstanding + References No definition available. + Details
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- Definition The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date. + 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 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date. + 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 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date. + 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 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition The maximum balance outstanding at any month end during the period as of the Balance Sheet date. + 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 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer. + 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 210.9-03.16) -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 942 -SubTopic 470 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64702-112823 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details
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- Definition The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date. + 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(13)(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of Federal Home Loan Bank (FHLB) advances which have fixed interest rates maturing between the next fiscal year and the fifth fiscal year following the latest fiscal year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601 + Details
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