Commitments and Contingencies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Amount outstanding under letters of credit	$ 1,303
Long Term Purchase Commitment [Line Items]
Unconditional purchase obligations, term	3 years
Unconditional purchase obligations	$ 61,280
Minimum
Long Term Purchase Commitment [Line Items]
Unconditional purchase obligations, term	1 year
Maximum
Long Term Purchase Commitment [Line Items]
Unconditional purchase obligations, term	3 years