Related Party Transactions (Details 2) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Derivative notional amount	$ 170,705,000,000	$ 177,428,000,000
Transferred Entities
Related Party Transaction [Line Items]
Derivative notional amount	1,500,000,000	1,600,000,000
Accumulated unrealized gain on derivatives	76,000,000	72,000,000
Transferred Entities \| Affiliated Entity
Related Party Transaction [Line Items]
Guaranteed balance	1,000,000	$ 0
Transferred Entities \| Unsecured Debt
Related Party Transaction [Line Items]
Maximum borrowing capacity	1,900,000,000
Transferred Entities \| Secured Debt \| Affiliated Entity
Related Party Transaction [Line Items]
Maximum borrowing capacity	$ 475,000,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Accumulated Unrealized Gain (Loss) on Derivatives

+ References

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- Definition

Securities Sold under Agreements to Repurchase, Guaranteed Balance

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

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