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Trading Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule of Trading Securities [Line Items] |  |
Trading securities | $ 2,110,585 | $ 1,623,921
Trading Securities, Net Unrealized Gain (Loss) | 22,846 | 2,359
U.S. government agency debentures [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 37,740 | 44,264
Trading Securities, Net Unrealized Gain (Loss) | 264 | 6
Residential agency mortgage-backed securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 1,922,725 | 1,504,651
Trading Securities, Net Unrealized Gain (Loss) | 26,195 | 2,293
Municipal and other tax-exempt securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 35,513 | 26,196
Trading Securities, Net Unrealized Gain (Loss) | (289) | 60
Asset-backed securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 58,278 | 14,084
Trading Securities, Net Unrealized Gain (Loss) | (2,381) | (21)
Other debt securities [Member] |  |
Schedule of Trading Securities [Line Items] |  |
Trading securities | 56,329 | 34,726
Trading Securities, Net Unrealized Gain (Loss) | $ (943) | $ 21

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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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