Variable Interest Entities - Schedule of Carrying Value of Assets and Liabilities of PEAKS Trust (Detail) - USD ($) $ in Thousands	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013	Feb. 28, 2013
Variable Interest Entity [Line Items]
Restricted cash	$ 2,768	$ 5,636	$ 5,819
PEAKS Trust student loans, less allowance for loan losses	7,420	7,730	7,307
PEAKS Trust student loans, excluding current portion, less allowance for loan losses	65,997	76,479	101,375
Total assets	778,487	806,851	767,578	$ 6,614
Current portion of PEAKS Trust senior debt	132,429	157,883	102,695
Other current liabilities	46,049	42,136	43,177	3,060
PEAKS Trust senior debt, excluding current portion	64,301	71,341	124,983
Total	661,756	$ 691,205	637,892	46,114
PEAKS Trust [Member]
Variable Interest Entity [Line Items]
Restricted cash	1,423		2,203	1,703
PEAKS Trust student loans, less allowance for loan losses	7,420		7,307	7,282
PEAKS Trust student loans, excluding current portion, less allowance for loan losses	65,997		101,375	104,834
Total assets	74,840		110,885	113,819
Current portion of PEAKS Trust senior debt	132,429		102,695	103,356
Other current liabilities	395		559	471
PEAKS Trust senior debt, excluding current portion	64,301		124,983	122,740
Total	$ 197,125		$ 228,237	$ 226,567

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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.18)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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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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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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