Valuation And Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Allowance for Doubtful Accounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at the beginning of the period	$ 3,989		$ 4,366		$ 5,628
Additions	2,969	[1]	2,281	[1]	2,361	[1]
Deduction	(2,546)		(2,658)		(3,623)
Balance at the end of the period	4,412		3,989		4,366
Valuation Allowance of Deferred Tax Assets
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at the beginning of the period	77		231		736
Additions	2,234	[1]	77	[1]	7	[1]
Deduction	0		(231)		(512)
Balance at the end of the period	$ 2,311		$ 77		$ 231

[1] Reductions in/charges to revenues and expenses.