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Derivative Financial Instruments - Schedule of Interest Rate Swaps, Floor Income Hedge (Details) - Interest rate swaps - floor income hedges - Interest rate swap - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Derivative [Line Items]
Notional amount	$ 3,000,000,000	$ 5,575,000,000
Weighted average fixed rate paid by the Company	1.37%	1.18%
2019
Derivative [Line Items]
Notional amount	$ 500,000,000	$ 3,250,000,000
Weighted average fixed rate paid by the Company	1.12%	0.97%
2020
Derivative [Line Items]
Notional amount	$ 1,500,000,000	$ 1,500,000,000
Weighted average fixed rate paid by the Company	1.01%	1.01%
2021
Derivative [Line Items]
Notional amount	$ 600,000,000	$ 100,000,000
Weighted average fixed rate paid by the Company	2.15%	2.95%
2022
Derivative [Line Items]
Notional amount	$ 250,000,000	$ 0
Weighted average fixed rate paid by the Company	1.65%
2023
Derivative [Line Items]
Notional amount	$ 150,000,000	$ 400,000,000
Weighted average fixed rate paid by the Company	2.25%	2.24%
2024
Derivative [Line Items]
Notional amount	$ 0	$ 300,000,000
Weighted average fixed rate paid by the Company		2.28%
2027
Derivative [Line Items]
Notional amount	$ 0	$ 25,000,000
Weighted average fixed rate paid by the Company		2.35%

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

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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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