Income Taxes - Net Operating Losses Carryforwards Expire (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
U.S. loss carryforwards	$ 252,927
State loss carryforwards	176,106
Foreign loss carryforwards	$ 178
Federal | Minimum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, expiration year	2031
Federal | Maximum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, expiration year	2033
State | Minimum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, expiration year	2014
State | Maximum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, expiration year	2033