Other Information - Additional Information (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenue [Line Items]
Revenues	$ 56,363,000	$ 43,549,000	$ 47,884,000	$ 49,831,000	$ 61,694,000	$ 52,204,000	$ 54,860,000	$ 52,675,000	$ 197,627,000	$ 221,433,000	$ 230,813,000
Other Expenses [Abstract]
Advertising Expense									9,500,000	15,300,000	14,300,000
Interest Paid										300,000	500,000
Income Taxes Paid									500,000	600,000	500,000
Domestic
Revenue [Line Items]
Revenues									187,400,000	211,600,000	224,300,000
Foreign Sources
Revenue [Line Items]
Revenues									$ 10,200,000	$ 9,800,000	$ 6,500,000