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Other Borrowed Funds (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Federal Home Loan Bank advances |  |
Other borrowed funds | $ 1,195,225,000 | $ 733,375,000
Federal home loan bank advances maturing November 2027 |  |
Federal Home Loan Bank advances |  |
Other borrowed funds | 100,000,000 |
Federal home loan Bank advances maturing December 20207 |  |
Federal Home Loan Bank advances |  |
Other borrowed funds | 150,000,000 |
Federal Home Loan Bank advances - short-term |  |
Federal Home Loan Bank advances |  |
Other borrowed funds | $ 945,225,000 | $ 583,375,000
Rate on balance outstanding at year end (as a percent) | 1.44% | 0.66%
Average daily balance | $ 839,858,000 | $ 483,379,000
Average rate (as a percent) | 1.23% | 0.47%
Maximum amount outstanding at any month end | $ 1,043,250,000 | $ 600,875,000
Federal Home Loan Bank advances - long-term |  |
Federal Home Loan Bank advances |  |
Other borrowed funds | $ 250,000,000 | $ 150,000,000
Rate on balance outstanding at year end (as a percent) | 1.26% | 0.58%
Average daily balance | $ 51,644,000 | $ 150,000,000
Average rate (as a percent) | 1.26% | 0.58%
Maximum amount outstanding at any month end | $ 250,000,000 | $ 150,000,000

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- Definition Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages. + 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 + 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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