Stock-Based Compensation Plans, Stock Option Awards (Details) - Stock Options and Stock Appreciation Rights [Member] shares in Thousands	3 Months Ended
	Mar. 31, 2019 $ / shares shares
Shares [Roll Forward]
Outstanding, beginning balance (in shares) | shares	12,352
Granted (in shares) | shares	1,067
Exercised or settled (in shares) | shares	(2,271)
Forfeited (in shares) | shares	(57)
Outstanding, ending balance (in shares) | shares	11,091
Vested (in shares) | shares	8,879
Outstanding Weighted-Average Exercise Price [Abstract]
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 10.93
Granted (in dollars per share) | $ / shares	27.05
Exercised or settled (in dollars per share) | $ / shares	8.55
Forfeited (in dollars per share) | $ / shares	32.06
Outstanding, ending balance (in dollars per share) | $ / shares	12.86
Vested (in dollars per share) | $ / shares	$ 9.48