Restructuring and Other Special Charges and Related Liability Balances (Detail) (Restructuring November 2012 Plan, USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014
Restructuring Cost and Reserve [Line Items]
Accrual, Beginning Balance	$ 5,248
Cash Payments	(1,346)
Accrual, Ending Balance	3,902
Workforce reduction
Restructuring Cost and Reserve [Line Items]
Accrual, Beginning Balance	1,057
Cash Payments	(384)
Accrual, Ending Balance	673
Consolidation of office facilities
Restructuring Cost and Reserve [Line Items]
Accrual, Beginning Balance	4,063
Cash Payments	(845)
Accrual, Ending Balance	3,218
Other costs and professional fees
Restructuring Cost and Reserve [Line Items]
Accrual, Beginning Balance	128
Cash Payments	(117)
Accrual, Ending Balance	$ 11