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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
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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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