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

Average fixed interest rate related to the group of interest rate derivatives.

+ References

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Average variable interest rate related to the group of interest rate derivatives.

+ References

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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

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Derivative Instruments and Hedging Activities Schedule of Interest Rate Swap Receivers (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Jun. 30, 2017	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Derivative [Line Items]
Notional	$ 24,113,321,000	$ 18,802,500,000	$ 16,988,116,000	$ 22,062,904,000	$ 26,141,370,000	$ 21,998,381,000
Interest Rate Swap [Member] \| Short [Member]
Derivative [Line Items]
Notional	$ 4,405,676,000	$ 5,064,000,000
Weighted Average Variable Interest Rate	1.316%	0.941%
Weighted Average Fixed Interest Rate	2.093%	1.894%
Weighted Average Remaining Maturity	6 years 4 months 22 days	4 years 6 months 27 days
Interest Rate Swap [Member] \| Derivative Maturity Over One And Within Two Years From Balance Sheet Date [Member] \| Short [Member]
Derivative [Line Items]
Notional		$ 575,000,000
Weighted Average Variable Interest Rate		0.911%
Weighted Average Fixed Interest Rate		1.44%
Weighted Average Remaining Maturity		1 year 10 months 21 days
Interest Rate Swap [Member] \| Derivative Maturity Over Two And Within Three Years From Balance Sheet Date [Member] \| Short [Member]
Derivative [Line Items]
Notional	$ 508,273,000	$ 500,000,000
Weighted Average Variable Interest Rate	1.314%	0.882%
Weighted Average Fixed Interest Rate	1.582%	1.042%
Weighted Average Remaining Maturity	1 year 10 months 16 days	2 years 22 days
Interest Rate Swap [Member] \| Derivative Maturity Over Three And Within Four Years From Balance Sheet Date [Member] \| Short [Member]
Derivative [Line Items]
Notional	$ 200,000,000	$ 510,000,000
Weighted Average Variable Interest Rate	1.312%	0.881%
Weighted Average Fixed Interest Rate	1.642%	1.58%
Weighted Average Remaining Maturity	2 years 10 months 5 days	3 years 7 months 4 days
Interest Rate Swap [Member] \| Derivative Maturity Over Four Years From Balance Sheet Date [Member] \| Short [Member]
Derivative [Line Items]
Notional	$ 3,697,403,000	$ 3,479,000,000
Weighted Average Variable Interest Rate	1.316%	0.963%
Weighted Average Fixed Interest Rate	2.187%	2.137%
Weighted Average Remaining Maturity	7 years 2 months 14 days	5 years 6 months 8 days