Share-Based Compensation Plans - Summary of Activity Related to Restricted Stock Granted under Company's Incentive Plan (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Total Shares
Total Shares, Outstanding, Beginning Balance	460	776	993
Total Shares, Granted	152	163	192
Total Shares, Vested	(174)	(384)	(375)
Total Shares, Forfeited, canceled or expired	(16)	(95)	(34)
Total Shares, Outstanding, Ending Balance	422	460	776
Weighted Average Grant Date
Weighted Average Grant Date Fair Value, Beginning Balance	$ 63.28	$ 49.16	$ 38.32
Weighted Average Grant Date Fair Value, Granted	93.62	92.34	70.44
Weighted Average Grant Date Fair Value, Vested	56.14	65.57	32.46
Weighted Average Grant Date Fair Value, Forfeited, canceled or expired	82.11	71.60	44.51
Weighted Average Grant Date Fair Value, Ending Balance	$ 76.43	$ 63.28	$ 49.16