Shareholders' Equity (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 17, 2018
Equity, Class of Treasury Stock [Line Items]
Common stock, authorized	1,200,000,000	1,200,000,000
Preferred shares, authorized	20,000,000	20,000,000
2018 Program [Member]
Equity, Class of Treasury Stock [Line Items]
Amount approved to repurchase, shares, maximum			$ 20,000