Composition of Certain Balance Sheet Accounts - Schedule of Other Non-Current Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Other Assets, Noncurrent [Abstract]
Deferred cost of equipment revenue	$ 39,496	$ 14,159
Deposits on satellite and airborne equipment	13,914	10,800
Other	3,147	3,129
Total other non-current assets	$ 56,557	$ 28,088