General - Stock Compensation - Nonvested - Activity (Details)	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Restricted Stock Awards
Shares
Outstanding, beginning of period (in shares) | shares	54,314
Outstanding, end of period (in shares) | shares	54,314
Weighted Average Grant Date Fair Value
Outstanding, beginning of period (in dollars per share) | $ / shares	$ 77.33
Outstanding, end of period (in dollars per share) | $ / shares	$ 77.33
Restricted Stock Units (RSUs)
Shares
Outstanding, beginning of period (in shares) | shares	428,362
Awarded (in shares) | shares	275,619
Vested (in shares) | shares	(148,546)
Forfeited (in shares) | shares	(887)
Outstanding, end of period (in shares) | shares	554,548
Weighted Average Grant Date Fair Value
Outstanding, beginning of period (in dollars per share) | $ / shares	$ 65.83
Awarded (in dollars per share) | $ / shares	92.85
Vested (in dollars per share) | $ / shares	67.77
Forfeited (in dollars per share) | $ / shares	70.40
Outstanding, end of period (in dollars per share) | $ / shares	$ 78.73
Performance Based Restricted Stock Units ("PSUs")
Shares
Outstanding, beginning of period (in shares) | shares	278,945
Forfeited (in shares) | shares	(63,324)
Outstanding, end of period (in shares) | shares	215,621
Weighted Average Grant Date Fair Value
Outstanding, beginning of period (in dollars per share) | $ / shares	$ 99.80
Forfeited (in dollars per share) | $ / shares	141.61
Outstanding, end of period (in dollars per share) | $ / shares	$ 87.51