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Guarantees and Long Term Standby Purchase Commitments - Long-Term Standby Purchase Commitments (Details) - Long-Term Standby Purchase Commitments [Member] - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016
Guarantor Obligations [Line Items] |  |
Guarantor Obligations, Maximum Exposure, Undiscounted | $ 3,000.0 | $ 3,100.0
Weighted average remaining maturity, Loans underlying guarantees not held by transferor | 15 years 1 month 10 days | 15 years 1 month 10 days
Guarantee obligations issued after January 1, 2003 [Member] |  |
Guarantor Obligations [Line Items] |  |
Guarantor Obligations, Current Carrying Value | $ 31.8 | $ 31.8

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- Definition Weighted average remaining maturity, Loans underlying guarantees not held by transferor + References No definition available. + Details
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- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248 + Details
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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 Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248 + Details
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- Details
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- Details
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