Lease Obligations - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Option to extend	10 years
Option to terminate	1 year
Operating lease expense	$ 8.9	$ 12.3
Weighted average remaining lease term	5 years		5 years 3 months 4 days
Weighted average discount rate	6.53%		6.25%
Minimum
Lessee, Lease, Description [Line Items]
Remaining term	1 year
Interest rate	4.30%
Maximum
Lessee, Lease, Description [Line Items]
Remaining term	7 years
Interest rate	8.70%