Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Purchase and retirement of common stock (in shares)	34,090,566	16,606,157	33,953,127
Dividends declared on common stock (in dollars per share)	$ 0.40	$ 0.40	$ 0.40
Issuance of shares of common stock pursuant to employee stock plans (in shares)	1,682,202	1,709,140	2,166,861