Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Closed-ended terms for guarantees	8 years
Maximum potential future payments on guarantees	$ 40.9
Contingent liabilities, current	74.8	$ 69.5
Contingent liabilities, non-current	22.5	23.4
Errors and Omissions (E&O) claims and other claims
Loss Contingencies [Line Items]
Contingent liabilities	30.2	32.8
Workers' compensation
Loss Contingencies [Line Items]
Contingent liabilities	67.1	60.1
Insurance recoverable
Loss Contingencies [Line Items]
Contingent liabilities	$ 3.5	$ 3.9

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=118943654&loc=d3e12069-110248

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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=118942415&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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