Retirement Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Actual return	$ 17	$ 30
(Level 3)
Defined Benefit Plan Disclosure [Line Items]
Actual return	(5)
Estimated future employer contributions in next fiscal year	$ 21