Equity (Changes To Equity) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 714.4
Shares Paid for Tax Withholding for Share Based Compensation	345	11,920
Repurchase Agreements [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Repurchase Program, Authorized Amount	$ 1,000.0