Equity Compensation Plans and Share-Based Compensation - Restricted Stock Unit Award Activity (Details) - $ / shares shares in Thousands	1 Months Ended	12 Months Ended
Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Underlying Shares - Outstanding at beginning of year		357	254	157
Underlying Shares - Outstanding at end of year	373	373	357	254
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted-Average Exercise Price - Outstanding at beginning of year		$ 69.13	$ 59.53	$ 47.36
Weighted-Average Exercise Price - Outstanding at end of year	$ 77.40	$ 77.40	$ 69.13	$ 59.53
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Underlying Shares - Granted		238	109	102
Underlying Shares - Exercised		(117)	(10)	(10)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted-Average Exercise Price - Granted		$ 78.40	$ 86.86	$ 72.70
Weighted-Average Exercise Price - Vested		$ 48.25	$ 45.93	$ 45.93
Vesting period		3 years
Time Based Shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Underlying Shares - Granted		21	19	17
Underlying Shares - Exercised		(12)	(15)	(12)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted-Average Exercise Price - Granted		$ 84.93	$ 86.86	$ 72.70
Weighted-Average Exercise Price - Vested		$ 76.84	$ 73.78	$ 43.55
Vesting period		5 years	5 years	5 years
Performance-Based Canceled
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Underlying Shares - Exercised		(114)	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted-Average Exercise Price - Vested		$ 84.93	$ 0	$ 0
Grant date fair value of replacement performance-based awards	$ 72.37

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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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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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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).

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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.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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Weighted average grant-date fair value of non-vested options forfeited.

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