Guarantees - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Commitments And Guarantees [Line Items]
Short-term deferred revenues	$ 172,056,000		$ 172,056,000		$ 158,482,000
Long-term deferred revenue	88,112,000		88,112,000		91,061,000
Cost of providing services	37,300,000	35,500,000	110,700,000	102,200,000
Software Service, Support and Maintenance Arrangement
Commitments And Guarantees [Line Items]
Short-term deferred revenues	170,583,000		170,583,000		156,487,000
Long-term deferred revenue	$ 83,387,000		$ 83,387,000		$ 85,286,000
Software Products
Commitments And Guarantees [Line Items]
Warranty period of products			90 days
Hardware Products | Minimum
Commitments And Guarantees [Line Items]
Warranty period of products			1 year