Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss on write-downs of cost method investments	$ (15,000)	$ (1,114)		$ (15,161)	$ (1,364)
Impairment of goodwill		$ 248,600
Impairment of long-lived assets			$ 6,900
Vocational School Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss on write-downs of cost method investments	$ (15,000)