Segment Reporting - Assets by Geographic Region (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Fixed Assets	$ 312,122	$ 326,407
Total Assets	616,210	634,968
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Fixed Assets	308,923	323,361
Total Assets	597,467	617,878
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Fixed Assets	3,199	3,046
Total Assets	$ 18,743	$ 17,090