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Arrangements with Navient Corporation (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Apr. 30, 2014
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Related Party Transactions [Abstract] |  |
Remaining balance of indemnification receivable in connection with the spin-off | $ 5 | $ 27

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- Definition Deferred Tax Assets, Remaining Balance of Indemnification Receivable In Connection with The Spin-Off + References No definition available. + Details
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Balance Type: | debit
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- References No definition available. + Details
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Balance Type: | na
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