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Stock-Based Compensation - Narrative (Details) | 12 Months Ended
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Dec. 31, 2020 USD ($) plan $ / shares shares | Dec. 31, 2019 $ / shares shares | Dec. 31, 2018 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares available for issuance under the 2016 Plan (in shares) | 2,761,911 |  |
Unrecognized compensation expense for all nonvested awards | $ | $ 31,700,000 |  |
Weighted average period for recognition | 1 year 7 months 6 days |  |
Cash-settled SARs, outstanding (in shares) | 24,051 |  |
Stock-settled SARs, outstanding (in shares) | 3,628 |  |
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 |  |
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) | 3,793,218 |  |
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 | $ | $ 25,000 |  |
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) | 36,494 | 51,391 | 55,669
Restricted Stock |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted at target level (in shares) | 8,721 | 13,308 | 15,942
Granted at target level (in dollars per share) | $ / shares | $ 200.35 | $ 116.39 | $ 96.77
Annual Incentive Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Vesting period | 4 years |  |
Granted at target level (in shares) | 350 | 1,300 | 1,500
Granted at target level (in dollars per share) | $ / shares | $ 156.49 | $ 106.14 | $ 93.00
Conversion rate | 0.25 |  |
Share-based compensation arrangement by share-based payment award, equity instruments other than options, forfeited in period (in shares) | 0 | 0 | 200
Stock-settled PSU awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Granted at target level (in shares) | 53,659 | 84,309 | 102,307
Granted at target level (in dollars per share) | $ / shares | $ 177.31 | $ 103.40 | $ 90.45
Share-based compensation arrangement by share-based payment award, equity instruments other than options, forfeited in period (in shares) | 11,404 | 16,204 | 23,946
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) | 358,890 |  |
Number of deferred stock units payable in cash (in shares) | 6,274 |  |
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) | 10,302 |  |
Granted at target level (in dollars per share) | $ / shares | $ 194.29 |  |

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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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). + 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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- 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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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