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Debt - 2017 Senior Notes (Details) - 2027 Senior Notes - USD ($) | Feb. 21, 2017 | Sep. 30, 2021
--- | --- | ---
Debt |  |
Face amount | $ 1,000,000,000 |
Fair value of debt instrument |  | $ 1,104,500,000
Interest rate (as a percent) | 5.125% |
At any time and from time to time prior to December 15, 2026 |  |
Debt |  |
Redemption price (in percent) | 100.00% |
At any time on or after December 15, 2026 |  |
Debt |  |
Redemption price (in percent) | 100.00% |

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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