Acquisitions - Merger and Integration Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2013
Qelp [Member] | Other Items [Member] | General and Administrative [Member]
Business Acquisition [Line Items]
Transaction costs	$ 455
Alpine Access, Inc [Member]
Transaction and integration costs:
Total merger and integration costs		$ 2,114
Alpine Access, Inc [Member] | General and Administrative [Member]
Severance costs:
Severance costs		1,144
Transaction and integration costs:
Transaction and integration costs		444
Alpine Access, Inc [Member] | Direct Salaries and Related Costs [Member]
Severance costs:
Severance costs		526
Alpine Access, Inc [Member] | Americas [Member] | General and Administrative [Member]
Severance costs:
Severance costs		985
Alpine Access, Inc [Member] | Americas [Member] | Direct Salaries and Related Costs [Member]
Severance costs:
Severance costs		526
Alpine Access, Inc [Member] | Other Items [Member] | General and Administrative [Member]
Severance costs:
Severance costs		159
Transaction and integration costs:
Transaction and integration costs		$ 444