Valuation And Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Allowance for Doubtful Accounts
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance	$ 134	[1]	$ 88	[1]	$ 115	[1]
Additions (recoveries) –charged tocosts and expenses	114	[1]	79	[1]	(27)	[1]
Deductions	(144)	[1]	(33)	[1]
Ending Balance	104	[1]	134	[1]	88	[1]
Valuation Allowance of Deferred Tax Assets
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance	49,146	[2]	61,564	[2]	62,538	[2]
Additions (recoveries) –charged tocosts and expenses	(47,917)	[2]	(12,418)	[2]	(974)	[2]
Ending Balance	$ 1,229	[2]	$ 49,146	[2]	$ 61,564	[2]

[1] We record additions to the allowance for doubtful accounts based on historical collections, write-off experience, current economic trends, and changes in customer payment terms and other factors that may affect our ability to collect payments. Deductions principally reflect amounts charged off as uncollectible, less amounts recovered.

[2] Deferred tax assets are reduced by a valuation allowance when, in our opinion, it is more likely than not that the related benefit will not be realized.