Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2014	Dec. 31, 2013
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	$ 2,877	$ 8,371
Accounts receivable, allowance for doubtful accounts			$ 7,248	$ 8,695