Maximum target number of market stock units granted based on stock performance in percent.

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Minimum target number of market stock units granted based on stock performance in percent.

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Number of days for calculation of average closing stock price.

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Number of equal annual increments.

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- Definition

Number of share-based compensation plans pursuant to which awards are currently being made.

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Total number of shares of common stock for issuance.

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Ratio of total number of shares reserved under the plan.

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- Definition

Weighted-average period to recognize the cost of nonvested awards.

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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Number of shares authorized for issuance under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Share-Based Payments - Narrative (Details) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2015 shares	Dec. 31, 2021 USD ($) Increment plan $ / shares shares	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2013 Increment	Jun. 30, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award
Unrecognized compensation cost related to unvested share-based compensation		$ 235.5
Weighted-average period to recognize the cost of unvested awards		1 year 10 months 24 days
Number of share-based compensation plans pursuant to which awards are currently being made \| plan		3
Total intrinsic value of options exercised			$ 2.9	$ 4.2
Shares issued under ESPP (in shares) \| shares	6.2
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Share based payment arrangement, term		10 years
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period		1 year
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period		4 years
Market Stock Units (MSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Number of equal annual increments \| Increment		3			4
Percentage of earnings of the target number of units granted based on actual stock performance		0.00%			0.00%
Percentage of earnings of the target number of units granted based on actual stock performance		200.00%			150.00%
Number of days for calculation of average closing stock price		30 days
Total fair value of vested awards		$ 22.5	$ 26.9	$ 32.5
Granted (in dollars per share) \| $ / shares		$ 358.77	$ 398.61	$ 378.08
Cash Settled Performance Units (CSPUs)
Share-based Compensation Arrangement by Share-based Payment Award
Number of equal annual increments \| Increment		3
Percentage of earnings of the target number of units granted based on actual stock performance		0.00%
Percentage of earnings of the target number of units granted based on actual stock performance		200.00%
Number of days for calculation of average closing stock price		30 days
Cash settlement of awards upon vesting			$ 3.8	$ 10.6
Performance Units (PUs)
Share-based Compensation Arrangement by Share-based Payment Award
Number of equal annual increments \| Increment		3
Percentage of earnings of the target number of units granted based on actual stock performance		0.00%
Percentage of earnings of the target number of units granted based on actual stock performance		200.00%
Number of days for calculation of average closing stock price		30 days
Cash settlement of awards upon vesting			3.4	10.4
PSUs Settled in Stock
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period		3 years
Percentage of earnings of the target number of units granted based on actual stock performance		0.00%
Percentage of earnings of the target number of units granted based on actual stock performance		200.00%
Granted (in dollars per share) \| $ / shares		$ 276.61
PSUs Settled in Cash
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period		3 years
Percentage of earnings of the target number of units granted based on actual stock performance		0.00%
Percentage of earnings of the target number of units granted based on actual stock performance		200.00%
Number of days for calculation of average closing stock price		30 days
Time-Vested Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period		3 years
Total fair value of vested awards		$ 132.2	$ 140.5	$ 131.5
Granted (in dollars per share) \| $ / shares		$ 276.90	$ 318.87	$ 304.44
Time-Vested Restricted Stock Units (RSUs) \| Share-based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award
Vesting percentage		33.33%
Time-Vested Restricted Stock Units (RSUs) \| Share-based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award
Vesting percentage		33.33%
Time-Vested Restricted Stock Units (RSUs) \| Share-based Payment Arrangement, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award
Vesting percentage		33.33%
Directors Plan
Share-based Compensation Arrangement by Share-based Payment Award
Total number of shares of common stock for issuance (in shares) \| shares		1.6
Ratio of total number of shares reserved under the plan		1.5
2017 Omnibus Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award
Ratio of total number of shares reserved under the plan		1.5
Omnibus Plan number of shares authorized (in shares) \| shares						8.0