Segment Disclosures - Schedule of Revenue from External Customers (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 203,138	$ 239,790	$ 235,498	$ 269,998	$ 199,023	$ 224,249	$ 232,641	$ 266,090	$ 948,424	$ 922,003	$ 855,340
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									946,801	920,481	853,802
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									$ 1,623	$ 1,522	$ 1,538