v3.8.0.1

Debt - Interest Rate Swaps (Details) - USD ($) | Dec. 31, 2017 | Feb. 28, 2017 | Nov. 30, 2016 | Feb. 29, 2016
--- | --- | --- | --- | ---
February 15, 2021 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Derivative, notional amount | $ 600,000,000 |  |  | $ 600,000,000
Swap average, variable interest rate |  |  |  | 4.22%
May 15, 2022 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Derivative, notional amount | 500,000,000 |  |  |
February 15, 2024 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Derivative, notional amount | 1,000,000,000 |  |  | $ 1,000,000,000
Swap average, variable interest rate |  |  |  | 4.44%
January 15, 2025 |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Derivative, notional amount | 600,000,000 | $ 600,000,000 |  |
Derivative, interest rate |  | 2.53% |  |
Interest rate swap |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Derivative, notional amount | $ 2,700,000,000 |  |  |
Swap average, variable interest rate | 3.61% |  |  |
Weighted average interest rate, interest rate swap agreements | 4.99% |  |  |
$1,200 million 4.75% Senior notes, due January 15, 2025 | Senior Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Face amount | $ 1,200,000,000 |  | $ 1,200,000,000 |
Interest rate stated, percentage | 4.75% |  | 4.75% |
Five Point Seven Five Percent Senior Notes, Due June first twenty seventeen | Senior Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Face amount |  |  | $ 425,000,000 |
Interest rate stated, percentage |  |  | 5.75% |
Five Point Seven Five Percent Senior Notes, Due June first twenty seventeen | Senior Notes | Interest rate swap |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Derivative, notional amount |  |  | $ 250,000,000 |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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=6877327&loc=d3e13212-122682 + Details
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