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	$ 9,376	$ 6,676	$ 6,584
Addition Charged to cost and expenses	13,117	11,475	8,757
Addition Charged (credited) to other accounts	(201)	(520)
Deductions/ Other	(6,104)	(8,255)	(8,665)
Balance at end of year	16,188	9,376	6,676
Deferred tax valuation allowance [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	19,115	21,023	17,239
Addition Charged to cost and expenses	7,010	(1,908)	3,784
Addition Charged (credited) to other accounts
Deductions/ Other
Balance at end of year	$ 26,125	$ 19,115	$ 21,023