Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning Of Period	$ 6,987	$ 7,700	$ 6,580
Valuation Allowances and Reserves, Charged to Cost and Expense	5,152	4,860	4,156
Deductions	4,212	5,573	3,036
Balance at End of Period	$ 7,927	$ 6,987	$ 7,700