Property, Plant and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Internal-use software development cost	$ 36,300,000	$ 22,600,000
Internal-use software development cost, accumulated amortization	9,500,000	6,600,000
Amortization expense on assets recorded under capital leases	1,700,000	1,200,000	1,200,000
Accumulated depreciation and amortization, Capital lease assets	197,904,000	173,915,000
Related Party
Property, Plant and Equipment [Line Items]
Accumulated depreciation and amortization, Capital lease assets	5,800,000	4,800,000
Non-Related Party
Property, Plant and Equipment [Line Items]
Accumulated depreciation and amortization, Capital lease assets	$ 5,100,000	$ 4,400,000