Goodwill and Acquired Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2013

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of the Changes in the Carrying Amount of Goodwill

The changes in the carrying amount of goodwill for the years ended December 31, 2013 and 2012 were as follows (in thousands):

	December 31, 2013			December 31, 2012
Beginning balance	$	723,701		$	452,914
Additions	35,606			270,787
Disposals	(1,939		)	—
Ending balance	$	757,368		$	723,701

Schedule of Acquired Intangible Assets

Acquired intangible assets that are subject to amortization consisted of the following as of December 31, 2013 and 2012 (in thousands):

	December 31, 2013							December 31, 2012
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Completed technologies	$	65,631	$	(35,476	)	$	30,155	$	71,531	$	(32,842	)	$	38,689
Customer relationships	115,100		(75,563		)	39,537		104,700		(68,702		)	35,998
Non-compete agreements	7,950		(2,623		)	5,327		14,770		(7,645		)	7,125
Trademarks and trade names	3,400		(990		)	2,410		3,700		(958		)	2,742
Acquired license rights	490		(490		)	—		490		(490		)	—
Total	$	192,571	$	(115,142	)	$	77,429	$	195,191	$	(110,637	)	$	84,554