Business Combinations - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Feb. 17, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill	$ 615,438		$ 493,890	$ 490,196
LCS Facilities
Business Acquisition [Line Items]
Accounts receivable		$ 9,338
Prepaid expenses and other current assets		183
Property and equipment		119,726
Intangible assets		73,200
Total assets acquired		202,447
Accounts payable and accrued expenses		2,442
Total identifiable net assets		200,005
Goodwill		107,398
Total consideration paid		$ 307,403