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Trading Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Schedule of Trading Securities [Line Items] |  |
Trading securities | $ 1,675,212 | $ 1,956,923
Trading Securities, Net Unrealized Gain (Loss) | 3,941 | 10,969
U.S. government agency debentures [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 63,334 | 63,765
Trading Securities, Net Unrealized Gain (Loss) | 23 | 254
Residential agency mortgage-backed securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 1,480,458 | 1,791,584
Trading Securities, Net Unrealized Gain (Loss) | 3,851 | 9,966
Municipal and other tax-exempt securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 44,105 | 34,507
Trading Securities, Net Unrealized Gain (Loss) | (99) | (1)
Asset-backed securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 36,928 | 42,656
Trading Securities, Net Unrealized Gain (Loss) | 50 | 685
Other debt securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 50,387 | 24,411
Trading Securities, Net Unrealized Gain (Loss) | $ 116 | $ 65

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562 + Details
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