Leases - Operating future minimum lease payments (Details) $ in Millions	Dec. 31, 2020 USD ($)
Operating Leased Assets [Line Items]
2021	$ 96.0
2022	74.8
2023	59.4
2024	46.7
2025	33.0
Later years	133.4
Total Lease Payments	443.3
Less: Interest	98.9
Present value of lease liabilities	344.4
Facilities
Operating Leased Assets [Line Items]
2021	68.1
2022	56.2
2023	47.5
2024	39.9
2025	31.0
Later years	132.6
Total Lease Payments	375.3
Less: Interest	93.8
Present value of lease liabilities	281.5
Vehicles
Operating Leased Assets [Line Items]
2021	9.2
2022	5.7
2023	3.3
2024	1.4
2025	0.7
Later years	0.8
Total Lease Payments	21.1
Less: Interest	1.8
Present value of lease liabilities	19.3
Other
Operating Leased Assets [Line Items]
2021	18.7
2022	12.9
2023	8.6
2024	5.4
2025	1.3
Later years	0.0
Total Lease Payments	46.9
Less: Interest	3.3
Present value of lease liabilities	$ 43.6

Amount of lessee's undiscounted obligation for lease payment for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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+ References

No definition available.

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