Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Closed-ended terms for guarantees	7 years 4 months 24 days
Maximum potential future payments on guarantees	$ 38.3
Contingent liabilities, current	108.8	$ 74.8
Contingent liabilities, non-current	25.5	22.5
Errors and Omissions (E&O) claims and other claims
Loss Contingencies [Line Items]
Contingent liabilities	42.3	30.2
Workers' compensation
Loss Contingencies [Line Items]
Contingent liabilities	92.0	67.1
Insurance recoverable
Loss Contingencies [Line Items]
Loss contingency, receivable	$ 4.8	$ 3.5

Guarantor Obligations, Close-Ended Term

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

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+ References

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Amount of loss contingency liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

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Amount of loss contingency liability expected to be resolved after one year or beyond the normal operating cycle, if longer.

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Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

+ References

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-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 3
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