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Derivative Financial Instruments - Schedule of Basis Swap (Details) - 1:3 basis swaps - USD ($) | 3 Months Ended |
--- | --- | ---
Sep. 30, 2019 | Dec. 31, 2018
Derivative [Line Items] |  |
Notional amount | $ 7,150,000,000 | $ 10,000,000,000
Net proceeds from termination of derivatives | 500,000 |
2019 |  |
Derivative [Line Items] |  |
Notional amount | 0 | 3,500,000,000
2020 |  |
Derivative [Line Items] |  |
Notional amount | 1,000,000,000 | 1,000,000,000
2021 |  |
Derivative [Line Items] |  |
Notional amount | 250,000,000 | 250,000,000
2022 |  |
Derivative [Line Items] |  |
Notional amount | 2,000,000,000 | 2,000,000,000
Effective Start Date May 2020 |  |
Derivative [Line Items] |  |
Notional amount | 750,000,000 |
2023 |  |
Derivative [Line Items] |  |
Notional amount | 750,000,000 | 750,000,000
2024 |  |
Derivative [Line Items] |  |
Notional amount | 1,750,000,000 | 250,000,000
2026 |  |
Derivative [Line Items] |  |
Notional amount | 1,150,000,000 | 1,150,000,000
2027 |  |
Derivative [Line Items] |  |
Notional amount | 250,000,000 | 375,000,000
Notional amount, terminated | 125,000,000 |
2028 |  |
Derivative [Line Items] |  |
Notional amount | 0 | 325,000,000
Notional amount, terminated | 325,000,000 |
2029 |  |
Derivative [Line Items] |  |
Notional amount | 0 | 100,000,000
Notional amount, terminated | 100,000,000 |
2031 |  |
Derivative [Line Items] |  |
Notional amount | 0 | $ 300,000,000
Notional amount, terminated | $ 300,000,000 |

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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 + Details
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- Definition The net cash outflow or inflow for a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 + Details
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