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Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands | 12 Months Ended
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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

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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued 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). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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