Share-Based Associate Compensation Plans (Restricted Stock Unit Information) (Details) - Restricted Stock Units (RSUs) shares in Thousands	12 Months Ended
	Dec. 31, 2018 $ / shares shares
Service Based Shares
Nonvested shares
Beginning balance (in shares) | shares	843
Granted (in shares) | shares	314
Vested (in shares) | shares	(323)
Forfeited or canceled (in shares) | shares	(21)
Ending balance (in shares) | shares	813
Weighted-average grant-date fair value
Beginning balance (in dollars per share) | $ / shares	$ 56.16
Granted (in dollars per share) | $ / shares	65.31
Vested (in dollars per share) | $ / shares	49.23
Forfeited or canceled (in dollars per share) | $ / shares	61.44
Ending balance (in dollars per share) | $ / shares	$ 62.31
Performance Based Shares
Nonvested shares
Beginning balance (in shares) | shares	206
Granted (in shares) | shares	57
Vested (in shares) | shares	(81)
Forfeited or canceled (in shares) | shares	0
Ending balance (in shares) | shares	182
Weighted-average grant-date fair value
Beginning balance (in dollars per share) | $ / shares	$ 53.35
Granted (in dollars per share) | $ / shares	63.29
Vested (in dollars per share) | $ / shares	45.73
Forfeited or canceled (in dollars per share) | $ / shares	0.00
Ending balance (in dollars per share) | $ / shares	$ 59.83