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Stock-Based Compensation (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense on restricted stock	$ 31	$ 29	$ 24
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	9	11	1
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	$ 2	2	0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards, term (in years)	10 years
Unrecognized compensation expense	$ 7
Unrecognized compensation expense, weighted-average period of recognition (in years)	1 year 8 months 12 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 25
Unrecognized compensation expense, weighted-average period of recognition (in years)	2 years 1 month 6 days
Total fair value of shares of restricted stock that vested	$ 18	$ 12	$ 28
Cliff Vest \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	5 years
Cliff Vest \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	3 years
Cliff Vest \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	6 years
Ratably On Annual Basis \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	3 years
Ratably On Annual Basis \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	2 years
Ratably On Annual Basis \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	5 years