CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 2,351,000	$ 9,174,000
Private education loans, allowance for loan losses	0	0
Private education loans, excluding current portion, allowance for loan losses	$ 44,392,000	$ 29,349,000
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000us-gaap_PreferredStockSharesAuthorized	5,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	300,000,000us-gaap_CommonStockSharesAuthorized	300,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	37,068,904us-gaap_CommonStockSharesIssued	37,068,904us-gaap_CommonStockSharesIssued
Treasury stock, shares	13,619,010us-gaap_TreasuryStockShares	13,698,716us-gaap_TreasuryStockShares

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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