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Securities Fair Value Option Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
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Fair Value Option Securities [Line Items] |  |
Fair value option securities, Fair Value | $ 1,816,398 | $ 283,235
Fair value option securities, Net Unrealized Gain (Loss) | 19,515 | 2,766
U.S. Treasury [Member] |  |
Fair Value Option Securities [Line Items] |  |
Fair value option securities, Fair Value | 552,536 | 0
Fair value option securities, Net Unrealized Gain (Loss) | 927 | 0
Residential agency mortgage-backed securities [Member] |  |
Fair Value Option Securities [Line Items] |  |
Fair value option securities, Fair Value | 1,263,862 | 283,235
Fair value option securities, Net Unrealized Gain (Loss) | $ 18,588 | $ 2,766

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- Definition Fair value option securities represent securities the Company has elected to carry at fair value and separately identified on the balance sheet with changes in fair value recognized in earnings as they occur. Certain residential mortgage-backed securities issued by US government agencies are held as an economic hedge of changes in the fair value of mortgage servicing rights and related derivative contracts. In addition, other securities may be held to manage interest rate risk or for deferred compensation purposes. Securities held for interest rate risk management may be economically hedged by derivative contracts not designated as hedging instruments effectively modify these fixed rate securities into variable rate securities. + References No definition available. + Details
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- Definition [Line Items] for Fair Value Option Securities [Table] + References No definition available. + Details
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- Definition Fair Value Option Securities Unrealized Gain or Loss + References No definition available. + Details
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- Details
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- Details
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