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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Rate of weighted-average expected volatility for award under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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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Gross number of share options (or share units) granted during the period.

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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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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Long-Term Incentive Plan
Cash received from exercise of stock options	$ 11.6	$ 2.2	$ 36.7
Tax benefit from exercise of stock options	0.6	0.2	2.4
Intrinsic value of stock options exercised	$ 2.8	$ 0.8	$ 11.6
Volatility (as a percent)	29.10%	25.20%	22.80%
Options granted (shares)	2,600,000
Expected term (in years)	7 years 10 days	7 years 1 month 13 days	7 years 18 days
Chief Executive Officer
Long-Term Incentive Plan
Expected term (in years)	7 years	7 years	7 years
Non-executive employees
Long-Term Incentive Plan
Options granted (shares)	0
Director
Long-Term Incentive Plan
Expected term (in years)	8 years	8 years	8 years
Employee Stock Option
Long-Term Incentive Plan
Unrecognized compensation cost	$ 8.1
Weighted average recognition period	3 years 8 months 12 days
Expected term (in years)	10 years
Employee Stock Option \| Employees
Long-Term Incentive Plan
Award expiration period	10 years
Award vesting period	4 years
Award vesting (as a percent)	25.00%
Restricted Stock Units \| Chief Executive Officer
Long-Term Incentive Plan
Award vesting period	2 years
Award vesting (as a percent)	50.00%
Restricted Stock Units \| Employees
Long-Term Incentive Plan
Award expiration period	3 years
Restricted Stock Units \| Employees \| Tranche One
Long-Term Incentive Plan
Award vesting period	3 years
Award vesting (as a percent)	33.30%
Restricted Stock Units \| Employees \| Tranche Two
Long-Term Incentive Plan
Award vesting period	4 years
Award vesting (as a percent)	25.00%
Financial PSUs
Long-Term Incentive Plan
Award vesting (as a percent)	100.00%
Financial PSUs \| Minimum
Long-Term Incentive Plan
Stock units granted that recipients receive as performance based restricted stock units (as a percent)	0.00%	0.00%
Financial PSUs \| Maximum
Long-Term Incentive Plan
Stock units granted that recipients receive as performance based restricted stock units (as a percent)	200.00%	200.00%
TSR PSUs
Long-Term Incentive Plan
Award vesting period	3 years
Award vesting (as a percent)	100.00%
RSUs and PSUs
Long-Term Incentive Plan
Unrecognized compensation cost	$ 71.1
Weighted average recognition period	1 year 10 months 24 days
2015 LTIP
Long-Term Incentive Plan
Shares available for grant (shares)	15,700,000
2015 LTIP \| Non-employee Director
Long-Term Incentive Plan
Award vesting period	1 year
2015 LTIP \| Employee Stock Option \| Former CEO
Long-Term Incentive Plan
Long-term incentive award stock option awards (as a percent)	20.00%	20.00%
2015 LTIP \| Employee Stock Option \| Non-employee Director
Long-Term Incentive Plan
Award expiration period	10 years
2015 LTIP \| Restricted Stock Units \| Executives Officers excluding CEO
Long-Term Incentive Plan
Long-term incentive award restricted stock units (as a percent)	30.00%	30.00%
2015 LTIP \| Restricted Stock Units \| Former CEO
Long-Term Incentive Plan
Long-term incentive award restricted stock units (as a percent)	10.00%	10.00%
2015 LTIP \| Restricted Stock Units \| Senior Vice Presidents
Long-Term Incentive Plan
Long-term incentive award restricted stock units (as a percent)	50.00%	50.00%
2015 LTIP \| Financial PSUs
Long-Term Incentive Plan
Award vesting period	3 years
2015 LTIP \| Financial PSUs \| Executives Officers excluding CEO
Long-Term Incentive Plan
Long-term incentive award performance based restricted stock units (as a percent)	50.00%	50.00%
2015 LTIP \| Financial PSUs \| Former CEO
Long-Term Incentive Plan
Long-term incentive award performance based restricted stock units (as a percent)	50.00%	50.00%
2015 LTIP \| Financial PSUs \| Senior Vice Presidents
Long-Term Incentive Plan
Long-term incentive award performance based restricted stock units (as a percent)	50.00%	50.00%
2015 LTIP \| TSR PSUs \| Executives Officers excluding CEO
Long-Term Incentive Plan
Long-term incentive award performance based restricted stock units (as a percent)	20.00%	20.00%
2015 LTIP \| TSR PSUs \| Former CEO
Long-Term Incentive Plan
Long-term incentive award performance based restricted stock units (as a percent)	20.00%	20.00%