Contingencies, Commitments and Guarantees (Contingencies - Narrative) (Details) $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2021 USD ($) Claims	Sep. 30, 2020 Claims	Dec. 31, 2020 Claims
Minimum
Loss Contingencies
Loss Contingency, Range of Possible Loss, Portion Not Accrued	$ 0
Maximum
Loss Contingencies
Loss Contingency, Range of Possible Loss, Portion Not Accrued	$ 150
Asbestos Related Claims
Loss Contingencies
Asbestos-Related Claims | Claims	2,156	1,768	2,496