Acquisitions (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid	$ 52,688,000	$ 134,916,000	$ 205,794,000
Revenue	12,615
Net Income	1,350
Goodwill, Acquired During Period	45,665,000	156,115,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	57,425,000	82,360,000	35,822,000
Business Acquisition, Pro Forma Revenue	1,837,872	1,819,693
Business Acquisition, Pro Forma Net Income (Loss)	138,621	47,385
Business Acquisition Cost Of Acquired Entity Cash Paid To Bondholders	2,360,000	0	0
Business Acquisition, Contingent Consideration, at Fair Value	(2,200,000)	(1,500,000)
Vetstreet [Member]
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid			146,420,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets			8,565,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill			45,810,000
Goodwill, Acquired During Period			96,149,000
Business Acquisition, Purchase Price Allocation, Liabilities Assumed			(4,104,000)
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net			146,420,000
BrightHeart [Member]
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid			23,490,000
Fair value of total consideration transferred			50,019,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets			18,921,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill			8,796,000
Goodwill, Acquired During Period			39,806,000
Business Acquisition, Purchase Price Allocation, Liabilities Assumed			(17,504,000)
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net			50,019,000
Business Acquisition Cost Of Acquired Entity Cash Paid To Bondholders			26,048,000
Business Acquisition, Contingent Consideration, at Fair Value			481,000
Think Pets Inc [Member]
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid		7,468,000
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned		10,500,000
Business Acquisition Cost Of Acquired Entity Cash Paid For Hold Backs		1,050,000
Fair value of total consideration transferred		19,018,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets		2,093,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		7,221,000
Goodwill, Acquired During Period		12,155,000
Business Acquisition, Purchase Price Allocation, Liabilities Assumed		(2,451,000)
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		$ 19,018,000