Vesting Maximum, as a Percentage of Target, if Performance Goals are Achieved

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Amount of cost for defined contribution plan.

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

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Weighted-average period over which cost not yet recognized is expected to be recognized for 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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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Amount of noncash expense for 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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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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Number of shares authorized for issuance 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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Stock Incentive Compensation and Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	May 16, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of shares and share units vested	$ 46.3	$ 54.7	$ 41.6
Excess windfall tax benefit	0.2
Excess windfall tax benefit realized by the Company due to its net operating loss position in the taxable jurisdictions in which it operates		0.3	0.2
Total stock compensation expense recognized	40.0	43.7	41.4
Contributions to defined contribution pension plans	7.5	$ 6.7	$ 4.9
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to restricted stock awards	$ 66.7
Periods for recognition of compensation costs not yet recognized	1 year 8 months 12 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	3 years
Unrecognized compensation costs related to restricted stock awards	$ 4.9
Periods for recognition of compensation costs not yet recognized	1 year 8 months 12 days
Cash Settled Restricted Stock Unit (CSRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	4 years
2016 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares)				1,625,000
Number of shares available for grant (in shares)	800,000
2016 Long-Term Incentive Plan \| Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	4 years
Granted May 2018 \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting maximum as a percentage of target if performance goal are achieved	200.00%
Non-Employee Director Stock Incentive Plan \| Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive compensation, vesting period	3 years