Merger with Capella Education Company - Preliminary Fair Value of Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Aug. 01, 2018
Preliminary fair value of assets and liabilities
Goodwill	$ 732,799	$ 732,540
Capella Merger
Preliminary fair value of assets and liabilities
Cash and cash equivalents			$ 167,859
Marketable securities, current			31,419
Tuition receivable			38,803
Income tax receivable			163
Other current assets			8,496
Marketable securities, non-current			34,700
Property and equipment, net			53,182
Other assets			14,556
Intangible assets			349,800
Goodwill			725,999
Total assets acquired			1,424,977
Accounts payable and accrued expenses			(46,735)
Contract liabilities			(39,000)
Deferred income taxes			(100,044)
Other long term liabilities			(2,237)
Total liabilities assumed			(188,016)
Total consideration			$ 1,236,961