Income Taxes - Net Deferred Income Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Net deferred income tax assets (liabilities)
Accounts receivable	$ 8,754	$ 7,977
State taxes	5,482	2,632
Other liabilities and reserves	24,947	21,878
Other assets	34,731	33,606
Inventory	1,360	1,271
Net operating loss carryforwards	26,256	27,610
Share-based compensation	5,415	6,615
Intangible assets	(201,350)	(138,214)
Property and equipment	(24,419)	(22,753)
Unrealized loss on investments	0	(3)
Valuation allowance	(12,654)	(13,790)
Total non-current deferred income tax liabilities	$ (131,478)	$ (73,171)