Derivative Instruments and Hedging Activities Schedule of Interest Rate Swap Payers (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Notional	$ 49,205,497,000	$ 36,528,169,000	$ 31,226,878,000
Interest Rate Swap [Member] \| Long [Member]
Derivative [Line Items]
Notional	$ 30,913,709,000	$ 21,406,167,000
Weighted Average Variable Interest Rate	1.921%	2.651%
Weighted Average Remaining Maturity	3 years 1 month 20 days	3 years 9 months
Weighted Average Fixed Interest Rate	1.878%	1.978%
Interest Rate Swap [Member] \| Derivative Maturity Within One Year From Balance Sheet Date [Member] \| Long [Member]
Derivative [Line Items]
Notional	$ 3,640,000,000	$ 4,336,897,000
Weighted Average Variable Interest Rate	1.937%	2.565%
Weighted Average Remaining Maturity	25 days	24 days
Weighted Average Fixed Interest Rate	1.806%	1.769%
Interest Rate Swap [Member] \| Derivative Maturity Over One And Within Two Years From Balance Sheet Date [Member] \| Long [Member]
Derivative [Line Items]
Notional	$ 15,740,977,000	$ 3,640,000,000
Weighted Average Variable Interest Rate	1.91%	2.689%
Weighted Average Remaining Maturity	1 year 5 months 19 days	1 year 9 months 29 days
Weighted Average Fixed Interest Rate	1.681%	1.806%
Interest Rate Swap [Member] \| Derivative Maturity Over Two And Within Three Years From Balance Sheet Date [Member] \| Long [Member]
Derivative [Line Items]
Notional	$ 2,578,640,000	$ 4,117,000,000
Weighted Average Variable Interest Rate	1.901%	2.687%
Weighted Average Remaining Maturity	2 years 8 months 26 days	2 years 8 months 8 days
Weighted Average Fixed Interest Rate	1.911%	1.55%
Interest Rate Swap [Member] \| Derivative Maturity Over Three And Within Four Years From Balance Sheet Date [Member] \| Long [Member]
Derivative [Line Items]
Notional	$ 215,000,000	$ 2,470,000,000
Weighted Average Variable Interest Rate	1.91%	2.728%
Weighted Average Remaining Maturity	3 years 10 months 24 days	3 years 9 months
Weighted Average Fixed Interest Rate	3.057%	2.002%
Interest Rate Swap [Member] \| Derivative Maturity Over Four Years From Balance Sheet Date [Member] \| Long [Member]
Derivative [Line Items]
Notional	$ 8,739,092,000	$ 6,842,270,000
Weighted Average Variable Interest Rate	1.935%	2.636%
Weighted Average Remaining Maturity	7 years 2 months 12 days	7 years 7 months 6 days
Weighted Average Fixed Interest Rate	2.224%	2.495%
Forward Starting Interest Rate Swap [Member]
Derivative [Line Items]
Notional		$ 572,000,000.0
Weighted Average Fixed Interest Rate		2.80%

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

No definition available.

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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

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ 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.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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