Summary of Depreciation Expenses on Property Plant and Equipment and Accumulated Amortization of Capital Leases (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Depreciation and Other Amortization Expenses [Line Items]
Depreciation expense	$ 8,184	$ 9,612	$ 7,100
Accumulated amortization on capital leases	$ 1,653	$ 861