Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Stockholders' Equity [Abstract]
Shares repurchased (in shares)	120,372	701,899	90,415
Shares issued for stock-based awards (in shares)	300,974	198,694	376,142
Dividends on common stock (in dollars per share)	$ 4.21	$ 1.09	$ 0.97

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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