Goodwill and Other Intangible Assets (Other Intangible Assets) (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	182,107	128,543
Accumulated Amortization	85,160	88,955
Net Carrying Amount	96,947	39,588
Indefinite-lived Intangible Assets [Line Items]
Net Carrying Amount	516,753	541,278
Franchise Agreements [Member]
Indefinite-lived Intangible Assets [Line Items]
Net Carrying Amount	496,321	496,321
Wireless Licenses [Member]
Indefinite-lived Intangible Assets [Line Items]
Net Carrying Amount	0	22,150
Licensure and Accreditation [Member]
Indefinite-lived Intangible Assets [Line Items]
Net Carrying Amount	6,781	7,171
Other [Member]
Indefinite-lived Intangible Assets [Line Items]
Net Carrying Amount	13,651	15,636
Non-compete Agreements [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	2,500	13,540
Accumulated Amortization	1,590	12,622
Net Carrying Amount	910	918
Student and Customer Relationships [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	104,685	72,050
Accumulated Amortization	47,539	45,718
Net Carrying Amount	57,146	26,332
Databases and Technology [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	10,501	10,790
Accumulated Amortization	8,827	6,991
Net Carrying Amount	1,674	3,799
Trade Names and Trademarks [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	55,452	22,327
Accumulated Amortization	19,724	16,052
Net Carrying Amount	35,728	6,275
Other [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	8,969	9,836
Accumulated Amortization	7,480	7,572
Net Carrying Amount	1,489	2,264
Minimum [Member] | Non-compete Agreements [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	2 years	2 years
Minimum [Member] | Student and Customer Relationships [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	2 years	2 years
Minimum [Member] | Databases and Technology [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	3 years	3 years
Minimum [Member] | Trade Names and Trademarks [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	2 years	2 years
Minimum [Member] | Other [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	1 year	1 year
Maximum [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	10 years
Maximum [Member] | Non-compete Agreements [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	5 years	5 years
Maximum [Member] | Student and Customer Relationships [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	10 years	10 years
Maximum [Member] | Databases and Technology [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	5 years	5 years
Maximum [Member] | Trade Names and Trademarks [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	10 years	10 years
Maximum [Member] | Other [Member]
Amortized Intangible Assets [Line Items]
Useful Life (in years)	25 years	25 years