Fair Value Measurements, Financial Instruments, and Credit Risk - Carrying Values and Approximate Fair Values of Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Carrying Value | Significant Other Observable Inputs (Level 2) | Capital lease obligation (significant other observable inputs – level 2)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	$ 2,339	$ 3,042
Carrying Value | Significant Other Observable Inputs (Level 2) | USD Tranche (significant other observable inputs – level 2) | Term Loan
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	500,000	1,278,000
Carrying Value | Significant Other Observable Inputs (Level 2) | Euro Tranche (significant other observable inputs – level 2) | Term Loan
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	281,005	0
Carrying Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | 10.5% Senior Notes (quoted prices in active market for identical assets – level 1)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	440,000	440,000
Carrying Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | 7.0% Senior Notes (quoted prices in active market for identical assets – level 1)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	400,000	0
Carrying Value | Significant Unobservable Inputs (Level 3) | KFPC Loan Agreement (significant unobservable inputs – level 3)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	146,451	115,854
Fair Value | Significant Other Observable Inputs (Level 2) | Capital lease obligation (significant other observable inputs – level 2)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	2,339	3,042
Fair Value | Significant Other Observable Inputs (Level 2) | USD Tranche (significant other observable inputs – level 2) | Term Loan
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	505,940	1,293,975
Fair Value | Significant Other Observable Inputs (Level 2) | Euro Tranche (significant other observable inputs – level 2) | Term Loan
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	285,571	0
Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | 10.5% Senior Notes (quoted prices in active market for identical assets – level 1)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	504,975	501,600
Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | 7.0% Senior Notes (quoted prices in active market for identical assets – level 1)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	430,060	0
Fair Value | Significant Unobservable Inputs (Level 3) | KFPC Loan Agreement (significant unobservable inputs – level 3)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt	$ 146,451	$ 115,854