Stockholders' Equity (Deficit) - New Hire Equity Awards, Inducement Awards, Incentive Compensation and Other Awards (Details) $ / shares in Units, $ in Millions				3 Months Ended	12 Months Ended
	Sep. 26, 2018 shares	Sep. 18, 2017 $ / shares shares	Jan. 15, 2016 award $ / shares shares	Mar. 31, 2018 shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target level for the determination of performance goals and measures					100.00%
Additional awards of restricted stock | award			2
Performance achievement, percentage							200.00%
Vested (in share)					151,280	607,231	179,826
Expense related to the SLO program | $					$ 29.2	$ 44.9	$ 59.9
Share based compensation expense recognized period					15 months
Forfeited (in shares)					86,518	184,235	89,699
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as part of acquisition	20,000				20,000	0	0
2017 Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value on grant date (in usd per share) | $ / shares		$ 10.63
Time Vesting Inducement Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)			75,000
Fair value on grant date (in usd per share) | $ / shares			$ 39.95
2014 Special PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSU awards performance period					3 years
Percentage of reduction in amount earned based on free cash flow performance					25.00%
PSUs earned paid out period					2 years
Vested (in share)				658,783
SLO Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)					109,841	136,783	20,587
Increments of cash bonus, percent					25.00%
Restricted stock shares and restricted stock units included in SLO Award target					47,736
Expense related to the SLO program | $					$ 1.6	$ 1.1	$ 2.5
Performance Share Unit Awards For Acquisitions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)					30,506
Expense related to the SLO program | $					$ 0.3
Forfeited (in shares)					5,177
2017 Annual Incentive Plan | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)					23,478
Chief Operating Officer and CEO-Designate | Time Vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)		30,000
Fair value on grant date (in usd per share) | $ / shares		$ 42.89
Chief Operating Officer and CEO-Designate | 2017 Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units granted (in shares)		70,000
Target level for the determination of performance goals and measures		100.00%
Chief Operating Officer and CEO-Designate | Tranche One | 2017 Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative stockholder return rate		33.00%
Chief Operating Officer and CEO-Designate | Minimum | Tranche One | 2017 Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in usd per share) | $ / shares		$ 60.00
Chief Operating Officer and CEO-Designate | Minimum | Tranche Two | 2017 Performance-vesting New Hire Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in usd per share) | $ / shares		$ 75.00