Schedule 2 - Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for doubtful accounts receivable [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	$ 9,341	$ 6,542	$ 6,584
Addition Charged to cost and expenses	10,387	12,879	8,627
Addition Charged (credited) to other accounts	(13)	(501)	(4)
Deductions/ Other	(6,172)	(9,579)	(8,665)
Balance at end of year	13,543	9,341	6,542
Deferred tax valuation allowance [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	19,124	21,023	17,239
Addition Charged to cost and expenses	7,237	(1,899)	3,784
Addition Charged (credited) to other accounts
Deductions/ Other
Balance at end of year	$ 26,361	$ 19,124	$ 21,023