Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Balance Type:	credit
Period Type:	instant

- 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
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

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Debt - 2023 Senior Notes (Details) - USD ($)	1 Months Ended		12 Months Ended
Debt - 2023 Senior Notes (Details) - USD ($)	Sep. 30, 2018	Oct. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Aug. 31, 2015
Debt Instrument [Line Items]
Loss on debt extinguishment			$ 35,922,000	$ 10,926,000	$ 0
Payment of premium on debt extinguishment			$ (28,054,000)	$ (625,000)	$ 0
Senior Notes \| 2023 Senior Notes
Debt Instrument [Line Items]
Principal amount of debt at time of issuance						$ 500,000,000
Interest rate						7.875%
Repurchased amount	$ 475,000,000	$ 25,000,000
Loss on debt extinguishment	35,900,000	$ 1,100,000
Payment of premium on debt extinguishment	$ (28,100,000)