Employee Benefit Plans - Composition of Pension Plan Assets by Fair Value Level (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
U.S. Plan
Defined Benefit Plan Disclosure [Line Items]
Total	$ 33,573	$ 38,131
U.K. plan
Defined Benefit Plan Disclosure [Line Items]
Total	10,494	10,685
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Total	44,067	48,816	$ 49,402
CMRT | U.S. Plan
Defined Benefit Plan Disclosure [Line Items]
Total	33,573	38,131
Other | U.K. plan
Defined Benefit Plan Disclosure [Line Items]
Total	10,494	10,685
Level 1 | Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Total	10,494	10,685
Level 1 | Other | U.K. plan
Defined Benefit Plan Disclosure [Line Items]
Total	10,494	10,685
Level 2 | Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Total	33,573	38,131
Level 2 | CMRT | U.S. Plan
Defined Benefit Plan Disclosure [Line Items]
Total	$ 33,573	$ 38,131