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Securities Sold Under Repurchase Agreements (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Collateral Securities and Repurchase Borrowing agreements |  |
Average outstanding amount | $ 314,876,000 | $ 402,396,000
Maximum amount outstanding at any month end | 370,495,000 | 514,616,000
Collateralized Securities, Book Value of Securities Sold | 369,086,000 | 460,681,000
Collateralized securities, Fair Value of Securities Sold | 360,177,000 | 452,912,000
Repurchase Borrowing, Balance of Liability | $ 229,989,000 | $ 353,805,000
Repurchase Borrowing, Weighted Average Interest Rate (as a percent) | 0.87% | 1.32%
Overnight agreements |  |
Collateral Securities and Repurchase Borrowing agreements |  |
Collateralized Securities, Book Value of Securities Sold | $ 357,642,000 | $ 340,054,000
Collateralized securities, Fair Value of Securities Sold | 349,081,000 | 334,506,000
Repurchase Borrowing, Balance of Liability | $ 218,852,000 | $ 242,824,000
Repurchase Borrowing, Weighted Average Interest Rate (as a percent) | 0.85% | 0.25%
30 to 90 days |  |
Collateral Securities and Repurchase Borrowing agreements |  |
Collateralized Securities, Book Value of Securities Sold |  | $ 109,300,000
Collateralized securities, Fair Value of Securities Sold |  | 107,238,000
Repurchase Borrowing, Balance of Liability |  | $ 100,000,000
Repurchase Borrowing, Weighted Average Interest Rate (as a percent) |  | 3.99%
Over 90 days |  |
Collateral Securities and Repurchase Borrowing agreements |  |
Collateralized Securities, Book Value of Securities Sold | $ 11,444,000 | $ 11,327,000
Collateralized securities, Fair Value of Securities Sold | 11,096,000 | 11,168,000
Repurchase Borrowing, Balance of Liability | $ 11,137,000 | $ 10,981,000
Repurchase Borrowing, Weighted Average Interest Rate (as a percent) | 1.27% | 0.74%

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- Definition Represents the average amount of securities sold under repurchase agreements during the period. + References No definition available. + Details
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- Definition Represents the maximum balance outstanding at any month end during the period as of the balance sheet date. + References No definition available. + Details
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- Definition Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(m)(1)(i)(A)(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition Interest rate on the amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(m)(1)(i)(A)(ii)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition Market value of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(m)(1)(i)(A)(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=49176635&loc=d3e9760-107771 Reference 4: 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(1)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(m)(1)(a)(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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