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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, 2016 | Dec. 31, 2015 | Dec. 31, 2014
FHLB Fixed Rate Advances, Maturities Summary [Abstract] |  |  |
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, One To Five Years From Balance Sheet Date | 5.66% |  |
FHLB Fixed Rate Advances, Over 1 through 5 years | $ 1,000 |  |
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 | 6,000 |  |
Valuation adjustment from acquisition accounting | 493 |  |
FHLB Fixed Rate Advances, Total Amount | 6,493 |  |
Federal Home Loan Bank, Advances, Activity for Year [Abstract] |  |  |
FHLB Advances | 6,493 | $ 68,531 | $ 216,568
Average balance during the year | 79,673 | 70,678 | 44,876
Maximum month-end balance during the year | $ 250,515 | $ 242,556 | $ 216,568
Weighted average rate during the year | 0.80% | 0.68% | 0.74%
Weighted average rate at December 31 | 5.42% | 0.79% | 0.41%
FHLB Advances, Collateral Pledged | $ 1,510,514 | $ 1,399,201 |
FHLB Borrowing Capacity | 1,502,284 | 1,328,971 |
Federal Reserve Bank, Advances, Activity for Year [Abstract] |  |  |
Federal Reserve Bank, Advances, Collateral Pledged | 61,007 | 85,428 |
Federal Reserve Bank borrowing capacity | 61,007 | 85,428 |
Securities Investment [Member] |  |  |
Federal Reserve Bank, Advances, Activity for Year [Abstract] |  |  |
Federal Reserve Bank, Advances, Collateral Pledged | 32,795 | 47,516 |
Loans Receivable [Member] |  |  |
Federal Home Loan Bank, Advances, Activity for Year [Abstract] |  |  |
FHLB Advances, Collateral Pledged | 1,510,514 | 1,399,201 |
Commercial Loan [Member] |  |  |
Federal Reserve Bank, Advances, Activity for Year [Abstract] |  |  |
Federal Reserve Bank, Advances, Collateral Pledged | $ 28,212 | $ 37,912 |

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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 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://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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 the collateral pledged in support of federal home loan bank advances outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 + Details
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- Definition Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22 (b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64702-112823 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 3: http://www.xbrl.org/2003/role/presentationRef -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 Amount of Federal Home Loan Bank (FHLB) advances which have fixed interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 + Details
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