Income Taxes - Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Pension and postretirement benefits	$ 0
Deferred compensation	540
Restructuring related and other reserves	5
Alternative minimum tax and net operating loss carryforward	55,295
Intangible assets and goodwill	6,439
Other, net	1,692
Deferred tax assets before valuation allowance	63,971
Valuation allowance	(52,153)
Total deferred tax assets	11,818
Deferred tax liabilities:
Depreciation	4,991
Inventory	3,301
Pension	135
Excess of book basis over tax basis in investments	238
Convertible debt discount	17,773
Other, net	268
Total deferred tax liabilities	26,706
Net deferred tax (liabilities) assets	$ (14,888)
Predecessor
Deferred tax assets:
Pension and postretirement benefits		$ 809
Deferred compensation		595
Restructuring related and other reserves		4
Alternative minimum tax and net operating loss carryforward		91,769
Intangible assets and goodwill		11,647
Other, net		2,818
Deferred tax assets before valuation allowance		107,642
Valuation allowance		(79,908)
Total deferred tax assets		27,734
Deferred tax liabilities:
Depreciation		5,006
Inventory		20,172
Pension		0
Excess of book basis over tax basis in investments		0
Convertible debt discount		1,883
Other, net		292
Total deferred tax liabilities		27,353
Net deferred tax (liabilities) assets		$ 381