Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Allowance for loans losses	$ 1,388
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,125,000,000	1,125,000,000
Common stock, shares issued	453,000,000	451,000,000
Tax benefit for accumulated other comprehensive loss	$ 96	$ 30
Common stock held in treasury	267,000,000	236,000,000
FFELP Loans [Member]
Allowance for loans losses	$ 297	$ 64
Private Education Loans [Member]
Allowance for loans losses	$ 1,091	$ 1,048

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

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