Contingencies, Commitments and Guarantees (Asbestos Claims) (Details) - Asbestos Related Claims $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) Claims	Dec. 31, 2019 USD ($) Claims	Dec. 31, 2018 USD ($) Claims
Loss Contingencies [Line Items]
Asbestos personal injury claims at year end \| Claims	60,618	61,134	62,522
Number of new claims during the year \| Claims	2,496	3,187	3,359
Settlement payments during the year \| $	$ 52.9	$ 49.4	$ 51.4
Asbestos-related claims liability, ending balance \| $	$ 425.0

Amount of cash outflow to settle insured claims and pay costs incurred in the claims settlement process attributable to asbestos and environmental claims.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585

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Amount of loss contingency liability.

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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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The total number of new claims filed pertaining to a loss contingency during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 450
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Number of pending claims pertaining to a loss contingency.

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