Income Taxes - Summary of Activity in Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Balance, beginning of year	$ 33,948	$ 34,139
Decrease related to tax positions taken in prior years	(1,346)	(191)
Increase related to positions taken in the current year			34,139
Balance, end of year	$ 32,602	$ 33,948	$ 34,139