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Resale and Repurchase Agreements (Balance Sheet Offsetting) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Resale agreement [Member] |  |
Balance Sheet Offsetting [Line Items] |  |
Securities Purchased under Agreements to Resell, Gross | $ 1,050,000 | $ 1,050,000
Securities Purchased under Agreements to Resell, Liability | (200,000) | (200,000)
Securities purchased under agreements to resell, net | 850,000 | 850,000
Securities Purchased under Agreements to Resell, Not Subject to Master Netting Arrangement | 0 | 0
Securities Purchased under Agreements to Resell, Collateral, Obligation to Return Securities | (850,000) | (850,000)
Securities Purchased under Agreements to Resell, Amount Offset Against Collateral | 0 | 0
Repurchase agreement [Member] |  |
Balance Sheet Offsetting [Line Items] |  |
Securities Sold under Agreements to Repurchase, Gross | 2,256,113 | 2,030,737
Securities Sold under Agreements to Repurchase, Asset | (200,000) | (200,000)
Securities sold under agreements to repurchase, net | 2,056,113 | 1,830,737
Securities Sold under Agreements to Repurchase, Not Subject to Master Netting Arrangement | 0 | 0
Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Securities | (2,056,113) | (1,830,737)
Securities Sold under Agreements to Repurchase, Amount Offset Against Collateral | $ 0 | $ 0

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- Definition Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale 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. Reflects the net of Securities Purchased Under Agreements to Resell gross assets and liabilities. + References No definition available. + Details
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- Definition Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Reflects the net of Securities Sold Under Agreements to Repurchase gross liabilities and assets. + References No definition available. + Details
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- Definition Amount, after effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price offset against an obligation to return collateral. Includes assets 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 50 -Paragraph 3 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313 + Details
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- Definition Amount of obligation to return securities collateral under master netting arrangements that have not been offset against securities purchased under agreement to resell. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313 + Details
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- Definition Amount, before effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313 + Details
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- Definition Amount of liability associated with funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226003-175313 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 (b) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Amount, after 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 offset against a right to receive collateral. 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 13 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313 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 (e) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Amount of asset associated with 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226003-175313 + Details
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