Defined Contribution Plans	12 Months Ended
Dec. 31, 2020
Retirement Benefits [Abstract]
Defined Contribution Plans	Defined Contribution Plans We participate in a defined contribution plan which is intended to qualify under section 401(k) of the Internal Revenue Code. The Sallie Mae 401(k) Savings Plan covers substantially all employees. After six months of service, we match 100 percent of the first 5 percent of contributions for eligible employees. For the years ended December 31, 2020, 2019 and 2018, we contributed $8 million, $7 million and $5 million, respectively, to this plan.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

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-Name Accounting Standards Codification
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