Share-Based Compensation Plans (Schedule of Nominal Cost Option) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020
Nominal Cost Options
Outstanding, beginning balance (in shares)	14,878,000
Granted (in shares)	0
Exercised (in shares)	0
Forfeited (in shares)	0
Outstanding, ending balance (in shares)	0	0
Nominal Cost Options
Nominal Cost Options
Outstanding, beginning balance (in shares)		1,994,000
Granted (in shares)		117,000
Exercised (in shares)		(425,000)
Forfeited (in shares)		(139,000)
Outstanding, ending balance (in shares)	1,547,000	1,547,000
Weighted-Average Modification-Date Fair Value
Outstanding, beginning balance (in dollars per share)		$ 12.06
Exercised (in dollars per share)		16.86
Exercised (in dollars per share)		(15.43)
Forfeited (in dollars per share)		(11.83)
Outstanding, ending balance (in dollars per share)	$ 11.51	$ 11.51