Summary of Significant Accounting Policies (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Amortizable intangible assets
Gross carrying amount	$ 987,390		$ 987,390
Accumulated amortization	(319,201)		(319,201)
Net carrying amount	668,189		668,189
Amortization expense associated with amortizable intangible assets (including deferred financing costs)	14,332	10,973	27,958	22,989
Customer Relationships and Acquisition Costs
Amortizable intangible assets
Gross carrying amount	920,319		920,319
Accumulated amortization	(296,671)		(296,671)
Net carrying amount	623,648		623,648
Core Technology
Amortizable intangible assets
Gross carrying amount	3,811		3,811
Accumulated amortization	(3,624)		(3,624)
Net carrying amount	187		187
Trademarks and Non-Compete Agreements
Amortizable intangible assets
Gross carrying amount	6,586		6,586
Accumulated amortization	(4,602)		(4,602)
Net carrying amount	1,984		1,984
Deferred Financing Costs
Amortizable intangible assets
Gross carrying amount	56,674		56,674
Accumulated amortization	(14,304)		(14,304)
Net carrying amount	$ 42,370		$ 42,370