Restructuring - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Pre-tax restructuring expenses related to restructuring initiative	$ 2,581		$ 7,519
Restructuring liabilities		1,332		10,887
2011 Restructuring initiative
Restructuring Cost and Reserve [Line Items]
Pre-tax restructuring expenses related to restructuring initiative	$ 2,600		$ 7,500
Number of employees		406
Expected Severance payments period		6 months