Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Allowance for loans losses	$ 1,218	$ 1,286
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,125,000,000	1,125,000,000
Common stock, shares issued	450,000,000	445,000,000
Tax (benefit) expense for accumulated other comprehensive (loss) income	$ (27)	$ 35
Common stock held in treasury	220,000,000	198,000,000
FFELP Loans [Member]
Allowance for loans losses	$ 67	$ 76
Private Education Loans [Member]
Allowance for loans losses	$ 1,151	$ 1,201

Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss) attributable to parent.

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Face amount or stated value per share of common stock.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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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