Acquisitions - Allocation of Purchase Price (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill	$ 1,790,035	$ 1,768,949
Framehawk, Inc. [Member]
Business Acquisition [Line Items]
Current assets	569
Other assets	0
Property and equipment	36
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	14,000
Goodwill	14,575
Assets acquired	29,180
Current liabilities assumed	(748)
Long-term liabilities assumed	3,766
Deferred tax liabilities, non-current	(259)
Net assets acquired	24,407
Other 2014 Acquisition [Member]
Business Acquisition [Line Items]
Current assets	1,196
Other assets	9
Property and equipment	10
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	14,200
Goodwill	7,109
Assets acquired	22,524
Current liabilities assumed	(1,781)
Long-term liabilities assumed	0
Deferred tax liabilities, non-current	(2,743)
Net assets acquired	$ 18,000