Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) plan $ / shares shares	Dec. 31, 2020 $ / shares shares	Dec. 31, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance under the 2016 Plan (in shares)	2,052,885
Unrecognized compensation expense for all nonvested awards \| $	$ 37,300
Weighted average period for recognition	1 year 6 months
Deferred Compensation, Share-based Payments
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation conversion unit (in shares)	1
Number of deferred compensation plans \| plan	2
Number of deferred stock units (in shares)	406,361
Number of deferred stock units payable in cash (in shares)	8,390
Deferred Compensation, Share-based Payments \| Non-Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target level (in shares)	6,034	10,302
Granted at target level (in dollars per share) \| $ / shares	$ 338.38	$ 194.29
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reduced for each award granted (in shares)	1
Awards, expiration period	10 years
Award Types Other than Stock Options and Stock Appreciation Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reduced for each award granted (in shares)	2.5
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards, expiration period	10 years
Vesting period	4 years
Stock-settled PSU awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target level (in shares)	37,701	53,659	84,309
Granted at target level (in dollars per share) \| $ / shares	$ 333.58	$ 177.31	$ 103.40
Employee Stock Purchase Plan (ESPP)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance under the 2016 Plan (in shares)	3,766,202
Percentage of current market price for sales to eligible employees	85.00%
Limitation on payroll deductions of employee's base salary, percent	25.00%
Limitation on payroll deductions of employee's base salary, amount \| $	$ 25
Maximum number of shares per employee (in shares)	2,000
Maximum number of shares per employee, per year (in shares)	8,000
Purchases of shares (in shares)	27,016	36,494	51,391
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target level (in shares)	6,002	8,721	13,308
Granted at target level (in dollars per share) \| $ / shares	$ 312.41	$ 200.35	$ 116.39