Long-Term and Other Debt - Terms of Outstanding Debt (Details)	1 Months Ended	3 Months Ended
	Feb. 28, 2017	Dec. 31, 2017
Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
First lien leverage ratio, period one maximum		6.0
Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
First lien leverage ratio, period one maximum	5.5
Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
First lien leverage ratio, period one maximum	5.0