Schedule of Balances Related to Property and Equipment (Detail) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Land	$ 3,200,000	$ 3,200,000
Building and leasehold improvements	25,600,000	25,200,000
Equipment and furniture	127,800,000	117,300,000
Computer software	113,300,000	97,100,000
Property and equipment, Gross	269,900,000	242,800,000
Less: accumulated depreciation	(113,154,000)	(94,266,000)
Property and equipment, Net	$ 156,709,000	$ 148,536,000