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

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.

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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

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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Fair Value Measurements Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Aug. 20, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Properties held for sale, net	$ 5,040		$ 111,700
6.50% Senior Notes due 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.50%
6.125% Senior Notes due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.125%
6.50% Senior Notes due 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.50%
5.0% Senior Notes due 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	5.00%
5.625% Senior Notes due 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	5.625%
6.75% Senior Notes due 2026
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.75%
Senior Notes \| 6.50% Senior Notes due 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.50%
Principal Amount	$ 0		344,611
Long-term Debt, Fair Value	$ 0		351,682
Senior Notes \| 6.125% Senior Notes due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.125%
Principal Amount	$ 476,796		561,796
Long-term Debt, Fair Value	$ 491,076		571,627
Senior Notes \| 6.50% Senior Notes due 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.50%
Principal Amount	$ 0		394,985
Long-term Debt, Fair Value	$ 0		403,434
Senior Notes \| 5.0% Senior Notes due 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	5.00%
Principal Amount	$ 500,000		500,000
Long-term Debt, Fair Value	$ 491,000		483,440
Senior Notes \| 5.625% Senior Notes due 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	5.625%
Principal Amount	$ 500,000		500,000
Long-term Debt, Fair Value	$ 498,125		494,355
Senior Notes \| 6.75% Senior Notes due 2026
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.75%
Principal Amount	$ 500,000		500,000
Long-term Debt, Fair Value	$ 522,150		516,350
Senior Notes \| 6.625% Senior Notes due 2027
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	6.625%
Principal Amount	$ 500,000	$ 500,000	0
Long-term Debt, Fair Value	$ 517,250		0
Convertible Debt [Member] \| 1.50% Senior Convertible Notes Due 2021 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, interest rate, stated percentage	1.50%
Principal Amount	$ 172,500		172,500
Long-term Debt, Fair Value	$ 191,044		$ 168,291