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Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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Summary of Significant Accounting Policies (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2011 ac Instrument	Sep. 30, 2011 ac Instrument	Sep. 30, 2010	Dec. 31, 2010 Instrument	Jun. 30, 2011	Jun. 30, 2010 Instrument	Jun. 30, 2009 Instrument
Derivative Contract Details (Textual) [Abstract]
Inception date of derivative agreements		Apr. 01, 2009
Maturity date of derivative agreements		Mar. 01, 2016
Due to related parties	$ 464	$ 464		$ 10,346
Summary of Significant Accounting Policies (Textual) [Abstract]
Average days from the date of receipt in which funds remain as restricted cash and cash equivalents		60 to 90 Days
Amount agreed to pay to settle the qui tam matter as restricted cash					5,200
Pledged collateral as noncurrent restricted cash				760
Reduced pledge collateral	555	555
Number of derivative instruments held	2	2		2		2	2
Loss on derivatives included as a component of other comprehensive income, net of taxes		53	420
Interest expense on derivatives related to credit risk		13
Area of the Company's campus in Phoenix, Arizona	110	110
Percent of financial aid earn by student		100.00%
Period for write off inactive student accounts	150 days
Reduction in revenue due to scholarships offered to students		51,963	39,525
Collaboration agreement cost				8,500
Arrangement expense		612	7,694
Lease termination fee payable to old landlord		1,093
Lease termination fee	922	922
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative Contract Details (Textual) [Abstract]
Fair value of interest rate swap is a liability ,which is included in other non current liability	698	698		686
Interest Rate Corridor [Member]
Derivative Contract Details (Textual) [Abstract]
Inception date of derivative agreements		Jul. 01, 2009
Maturity date of derivative agreements		Apr. 30, 2014
Notional amount of interest rate swap	10,841	10,841
Fair value of interest rate corridor included in other assets	1	1		27
Interest rate payable on interest rate corridor if 30 Day LIBOR is less than 4%	30 Day LIBOR	30 Day LIBOR	30 Day LIBOR	30 Day LIBOR
Interest rate payable on interest rate corridor 30 Day LIBOR equal to 4% through 6%	4.00%	4.00%	4.00%	4.00%
Interest rate payable on interest rate corridor 30 Day LIBOR exceeds 6%	30 Day LIBOR less 2%	30 Day LIBOR less 2%	30 Day LIBOR less 2%	30 Day LIBOR less 2%
Interest Rate Swap [Member]
Derivative Contract Details (Textual) [Abstract]
Inception date of derivative agreements		May 01, 2010
Maturity date of derivative agreements		Apr. 30, 2014
Notional amount of interest rate swap	10,841	10,841
Interest rate receivable on interest rate swap amortizing notional amount	30 Day LIBOR	30 Day LIBOR	30 Day LIBOR	30 Day LIBOR
Fixed Interest rate payable on interest rate swap amortizing notional amount	3.245%	3.245%	3.245%	3.245%
Mind Streams [Member]
Derivative Contract Details (Textual) [Abstract]
Due to related parties	$ 206	$ 206		$ 9,367