Other Assets (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Assets, Noncurrent Disclosure [Abstract]
Deposits	$ 30.7	$ 23.6
Deferred profit sharing asset	10.7	10.9
Income tax receivable	7.3	17.1
Derivative instruments	20.4	5.0
Equity method investment in unconsolidated entities	4.9	5.0	$ 4.9
Stop loss insurance receivable	14.5	17.0
Cash surrender value of life insurance policies	0.9	0.9
Indemnification asset	17.5	20.6
Debt issue costs	6.0	5.5
Marketable securities	24.8	12.0
Other	62.7	49.4
Other assets	$ 200.4	$ 167.0

The amount of indemnification assets (amounts to be reimbursed if and when certain assumed liabilities are paid) recognized at the acquisition date of a business combination.

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) of amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

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Amount of investment in marketable security, classified as noncurrent.

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Amount of other miscellaneous assets.

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Amount of noncurrent assets classified as other.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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