Stock-Based Compensation and Equity - Restricted and Conditional Awards (Details)	6 Months Ended
Jun. 30, 2020 $ / shares shares
RSA and RSU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares
Nonvested, beginning balance - shares \| shares	283,977
Granted - shares \| shares	123,944
Vested - shares \| shares	(144,520)
Forfeited - shares \| shares	(5,555)
Adjustments - shares \| shares	0
Nonvested, ending balance - shares \| shares	257,846
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Nonvested, beginning balance, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 68.51
Granted, weighted average grant date fair value (in dollars per share) \| $ / shares	83.26
Vested, weighted average grant date fair value (in dollars per share) \| $ / shares	68.46
Forfeited, weighted average grant date fair value (in dollars per share) \| $ / shares	71.69
Adjustments, weighted average grant date fair value (in dollars per share) \| $ / shares	0
Nonvested, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 75.56
PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares
Nonvested, beginning balance - shares \| shares	331,242
Granted - shares \| shares	90,518
Vested - shares \| shares	(156,838)
Forfeited - shares \| shares	(6,715)
Adjustments - shares \| shares	(25,522)
Nonvested, ending balance - shares \| shares	232,685
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value
Nonvested, beginning balance, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 80.90
Granted, weighted average grant date fair value (in dollars per share) \| $ / shares	104.65
Vested, weighted average grant date fair value (in dollars per share) \| $ / shares	80.42
Forfeited, weighted average grant date fair value (in dollars per share) \| $ / shares	88.94
Adjustments, weighted average grant date fair value (in dollars per share) \| $ / shares	62.86
Nonvested, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 91.42

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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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.

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 net total number of shares (or other type of equity) under an equity-based award plan, other than a stock option plan, that were granted, vested and forfeited during the reporting period.

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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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-Publisher FASB
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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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