Shareholders' Equity (Narrative) (Details) - USD ($) shares in Millions, $ in Billions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jun. 01, 2018
Shareholders' Equity Disclosure [Line Items]
Cash Dividends Paid to Parent, Consolidated Subsidiaries	$ 5.6	$ 3.7
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	22.7
Statutory Accounting Practices, Statutory Capital and Surplus Required	9.7
Stock Repurchase Program, Number of Shares Authorized to be Repurchased			100
Extraordinary Dividends [Member]
Shareholders' Equity Disclosure [Line Items]
Cash Dividends Paid to Parent, Consolidated Subsidiaries	$ 1.3	$ 1.1