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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+ References

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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

Amount of transactions with related party during the financial reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
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-Section 50
-Paragraph 1
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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.

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Related Party Transactions - Narrative (Details) - USD ($) $ in Millions	Jul. 01, 2017	Sep. 30, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Derivative notional amount		$ 177,086	$ 177,428
Affiliated Entity
Related Party Transaction [Line Items]
Shares transferred to BTMU and MUFG	3,267,433
Transferred Entities
Related Party Transaction [Line Items]
Derivative notional amount		2,700	1,600
Accumulated unrealized gain on derivatives		2	$ 72
Transferred Entities \| Unsecured Debt
Related Party Transaction [Line Items]
Maximum borrowing capacity		$ 1,400
Transfer of Assets \| Affiliated Entity
Related Party Transaction [Line Items]
Amounts transferred to remaining U.S. subsidiaries	$ 1,000
Transfer of Goodwill and Intangibles \| Affiliated Entity
Related Party Transaction [Line Items]
Amounts transferred to remaining U.S. subsidiaries	196
Transfer of Liabilities \| Affiliated Entity
Related Party Transaction [Line Items]
Amounts transferred to remaining U.S. subsidiaries	$ 601