Accounting for Stock-based Compensation - Cash-settled Restricted Stock Unit Activity (Details) - Cash Settled RSUs - USD ($)	12 Months Ended			24 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Non-vested Beginning Balance	241,481	296,233	337,406	337,406
Number of Shares, Granted	52,246	134,259	103,606
Number of Shares, Vested	(104,272)	(154,653)	(123,395)
Number of Shares, Cancelled	(23,195)	(34,358)	(21,384)
Number of Shares, Non-vested Ending Balance	166,260	241,481	296,233	241,481
Number of Shares, expected to vest in the future	149,894
Weighted-Average Grant Date Fair Value, Non-vested Beginning Balance	$ 65.06	$ 58.83	$ 47.73	$ 47.73
Weighted-Average Grant Date Fair Value, Granted	89.51	60.30	77.03
Weighted-Average Grant Date Fair Value, Vested	63.96	49.44	44.61
Weighted-Average Grant Date Fair Value, Cancelled	69.68	63.03	53.99
Weighted-Average Grant Date Fair Value, Non-vested Ending Balance	72.79	$ 65.06	$ 58.83	$ 65.06
Weighted-Average Grant Date Fair Value, expected to vest in the future	$ 72.34
Aggregate Intrinsic Value, Non-vested	$ 17,049,963,000
Aggregate Intrinsic Value, expected to vest in the future	$ 15,371,630,000