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Secured Borrowings Term to Original Maturity (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
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Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | $ 2,898,952 | $ 3,109,420
Less than 30 days |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 910,937 | 551,643
30 to 90 days |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 533,112 | 782,393
91 to 180 days |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 1,454,903 | 1,512,384
181 to 364 days |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 0 | 0
1 year or longer |  |
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items] |  |
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | $ 0 | $ 263,000

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729 + Details
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