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Stock-Based Compensation - Nonvested Performance-based Award Activity (Details) - $ / shares | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Non-Employee Directors | Deferred Compensation, Share-based Payments |  |  |
Non-vested PSU Awards [Roll Forward] |  |  |
Granted at target level (in shares) | 6,034 | 10,302 |
Non-vested PSU Awards, Weighted Average Fair Value [Roll Forward] |  |  |
Granted at target level (in dollars per share) | $ 338.38 | $ 194.29 |
Stock-settled PSU awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of shares to be issued upon conversion (in shares) | 144,488 |  |
Average remaining term of shares issued at conversion | 1 year |  |
Non-vested PSU Awards [Roll Forward] |  |  |
Outstanding, beginning (in shares) | 222,799 | 264,622 | 296,037
Granted at target level (in shares) | 37,701 | 53,659 | 84,309
Adjustments above/(below) target (in shares) | 50,965 | (14,004) | (50,556)
Vested and converted (in shares) | (143,465) | (70,074) | (48,964)
Forfeited (in shares) | (3,526) | (11,404) | (16,204)
Outstanding, ending (in shares) | 164,474 | 222,799 | 264,622
Non-vested PSU Awards, Weighted Average Fair Value [Roll Forward] |  |  |
Outstanding, beginning (in dollars per share) | $ 116.37 | $ 92.80 | $ 76.84
Granted at target level (in dollars per share) | 333.58 | 177.31 | 103.40
Adjustments above/(below) target (in dollars per share) | 93.38 | 77.02 | 83.89
Vested and converted (in dollars per share) | 272.65 | 173.22 | 102.51
Forfeited (in dollars per share) | 152.30 | 104.43 | 69.09
Outstanding, ending (in dollars per share) | $ 179.88 | $ 116.37 | $ 92.80
Stock-settled PSU awards | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Actual payout range | 0.00% |  |
Stock-settled PSU awards | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Actual payout range | 200.00% |  |
Cash-Settled PSU Awards |  |  |
Non-vested PSU Awards [Roll Forward] |  |  |
Outstanding, beginning (in shares) | 2,112 | 1,981 | 1,592
Granted at target level (in shares) | 163 | 732 | 806
Adjustments above/(below) target (in shares) | 311 | (99) | (206)
Vested and converted (in shares) | (877) | (502) | (211)
Forfeited (in shares) | (391) | 0 | 0
Outstanding, ending (in shares) | 1,318 | 2,112 | 1,981
Non-vested PSU Awards, Weighted Average Fair Value [Roll Forward] |  |  |
Outstanding, beginning (in dollars per share) | $ 130.13 | $ 93.28 | $ 79.48
Granted at target level (in dollars per share) | 320.12 | 190.71 | 102.51
Adjustments above/(below) target (in dollars per share) | 91.40 | 74.43 | 56.95
Vested and converted (in dollars per share) | 274.29 | 173.22 | 102.51
Forfeited (in dollars per share) | 135.64 | 0 | 0
Outstanding, ending (in dollars per share) | $ 169.53 | $ 130.13 | $ 93.28
Restricted Stock |  |  |
Non-vested PSU Awards [Roll Forward] |  |  |
Granted at target level (in shares) | 6,002 | 8,721 | 13,308
Non-vested PSU Awards, Weighted Average Fair Value [Roll Forward] |  |  |
Granted at target level (in dollars per share) | $ 312.41 | $ 200.35 | $ 116.39

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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + 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)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + 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)(3) -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 The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + 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)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options. + 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)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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 (e)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. + 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)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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