Chapter 11 Proceeds, Liquidity, and Ability to Continue as a Going Concern (Liabilities Subject to Compromise) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
6.625% senior subordinated notes due 2021 (including accrued interest as of the Petition Date)	$ 671,724
Accounts payable	735
Employee separation benefit plan obligations	22,624
Estimated Litigation Liability	45,000
Royalty suspense accounts payable	19,637
Liabilities subject to compromise	$ 759,720	$ 0

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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