Segment and Geographic Information - Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 337,499	$ 341,872	$ 354,473	$ 325,175	$ 321,802	$ 308,524	$ 297,686	$ 293,908	$ 1,359,019	$ 1,221,920	$ 1,333,570
Operating income (loss)	(3,956)	$ (75,009)	$ 21,659	$ 14,133	26,315	$ 20,505	$ 8,145	$ (4,139)	(43,173)	50,826	19,946
Long-lived assets	125,309				165,967				125,309	165,967	150,449
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									1,028,313	924,580	965,957
Operating income (loss)									(33,236)	28,048	(18,959)
Long-lived assets	93,472				140,099				93,472	140,099	124,120
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									139,734	129,291	174,827
Operating income (loss)									12,220	16,156	27,126
Long-lived assets	8,816				9,464				8,816	9,464	9,872
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									71,839	60,238	56,474
Operating income (loss)									(3,771)	981	3,217
Long-lived assets	13,435				7,575				13,435	7,575	7,268
Other foreign
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues									119,133	107,811	136,312
Operating income (loss)									(18,386)	5,641	8,562
Long-lived assets	$ 9,586				$ 8,829				$ 9,586	$ 8,829	$ 9,189