Variable Interest Entities - Schedule of Fair Value and Carrying Value of Assets and Liabilities of the CUSO (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014
Variable Interest Entity [Line Items]
Restricted cash	$ 6,936	$ 6,040		$ 2,768
Current portion of CUSO Student Loans	9,379	10,584		7,420
CUSO Student Loans, excluding current portion	69,724	80,292		65,997
Total assets	711,300	749,160		776,219
Current portion of CUSO secured borrowing obligation	19,750	20,813		0
Other current liabilities	27,288	27,050		46,233
CUSO secured borrowing obligation, excluding current portion	91,339	100,194		0
Total liabilities	556,205	601,155		$ 656,081
CUSO [Member]
Variable Interest Entity [Line Items]
Restricted cash	3,487	2,517	$ 2,738
Current portion of CUSO Student Loans	3,129	3,415	3,406
CUSO Student Loans, excluding current portion	18,787	20,390	23,793
Other assets	198	284	199
Total assets	25,601	26,606	30,136
Current portion of CUSO secured borrowing obligation	19,750	20,813	20,662
Other current liabilities	302	179	624
CUSO secured borrowing obligation, excluding current portion	91,339	100,194	101,880
Other liabilities	1,879	1,073	1,940
Total liabilities	$ 113,270	$ 122,259	$ 125,106

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

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The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.

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Aggregate carrying amount of current liabilities (due within one year or within the normal operating cycle if longer) not separately disclosed in the balance sheet. Includes costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered and of liabilities not separately disclosed.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

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Carrying value as of the balance sheet date of the portion of long-term, collateralized debt obligations due within one year or the operating cycle, if longer. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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