Chapter 11 Proceedings - Liabilities Subject to Compromise (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long term debt	$ 500,000	$ 0
Accounts payable and accrued liabilities	31,185	0
Liabilities subject to compromise	533,181	$ 0
Preliminary Valuation
Debt Instrument [Line Items]
Accounts payable and accrued liabilities	21,670
Accrued interest payable on 2024 Notes	9,515
Operating lease liabilities	1,996
Liabilities subject to compromise	533,181
Preliminary Valuation \| 2024 Notes
Debt Instrument [Line Items]
Long term debt	$ 500,000

Liabilities Subject To Compromise, Advances From Non-Operators

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Liabilities Subject To Compromise, Operating Lease Liabilities

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Total amount of liabilities subject to compromise.

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The amount of trade accounts payable included in liabilities subject to compromise.

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