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

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

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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.

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Amount, after accumulated amortization, of debt premium.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt - (Senior Notes) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 06, 2019
Debt Instrument [Line Items]
Debt issued	$ 3,070,459
Aggregate outstanding principal	3,266,383	$ 3,266,218
2021 Senior Notes \| Senior notes
Debt Instrument [Line Items]
Debt issued			$ 325,000
Interest rate			6.75%
Senior notes
Debt Instrument [Line Items]
Debt issued	775,000
Aggregate unamortized premium	$ 19,400
Senior notes \| 2024 Senior Notes
Debt Instrument [Line Items]
Debt issued			$ 325,000
Interest rate			6.625%
Senior notes \| 2025 Senior Notes
Debt Instrument [Line Items]
Interest rate			6.875%