Business Acquisitions - Additional Information (Detail)	1 Months Ended		1 Months Ended		1 Months Ended
	Jun. 01, 2012 Vlingo, Inc. USD ($)	Apr. 26, 2012 Transcend Services, Inc. USD ($)	Oct. 06, 2011 Swype, Inc. USD ($)	Jun. 15, 2011 Equitrac Corporation USD ($)	Jun. 30, 2012 SVOX AG EUR (€)	Jun. 16, 2011 SVOX AG USD ($)	Jun. 16, 2011 SVOX AG EUR (€)
Business Acquisition [Line Items]
Business acquisition, cash paid	$ 196,304,000	$ 332,253,000	$ 77,500,000	$ 161,950,000		$ 80,919,000	€ 57,000,000
Merger consideration deposited into escrow account	15,000,000
Business acquisition, escrow account period	12 months
Contingent consideration payments		332,300,000	25,000,000
Business acquisition, total purchase price			102,500,000
Business acquisition, contingent payment term			18 months
Business acquisition, purchase price	225,000,000	332,253,000	93,944,000	161,950,000		122,375,000	87,000,000
Business acquisition, contingent consideration and deferred payment			16,444,000			43,000,000	30,000,000
Payment for business acquisition contingent consideration					8,300,000
Business acquisition, contingent consideration and deferred payment, current							€ 21,700,000
Business acquisition, contingent consideration and deferred payment, due date						Dec. 31, 2012	Dec. 31, 2012