Commitments, Contingencies and Guarantees - Commitments and Contingencies (Details) $ in Millions	3 Months Ended
	Feb. 28, 2025 USD ($)
Commitments And Guarantee Obligations [Line Items]
2025	$ 10,078.2
2026	852.2
2027 and 2028	281.7
2029 and 2030	14.3
2031 and Later	172.6
Maximum Payout	$ 11,399.0
Repurchase obligation settlement period	3 days
Equity commitments
Commitments And Guarantee Obligations [Line Items]
2025	$ 28.2
2026	18.0
2027 and 2028	2.0
2029 and 2030	0.1
2031 and Later	172.6
Maximum Payout	220.9
Loan commitments
Commitments And Guarantee Obligations [Line Items]
2025	0.0
2026	332.2
2027 and 2028	4.9
2029 and 2030	0.0
2031 and Later	0.0
Maximum Payout	337.1
Loan purchase commitments
Commitments And Guarantee Obligations [Line Items]
2025	3,632.2
2026	0.0
2027 and 2028	0.0
2029 and 2030	0.0
2031 and Later	0.0
Maximum Payout	3,632.2
Forward starting reverse repos
Commitments And Guarantee Obligations [Line Items]
2025	3,767.4
2026	0.0
2027 and 2028	0.0
2029 and 2030	0.0
2031 and Later	0.0
Maximum Payout	3,767.4
Forward starting repos
Commitments And Guarantee Obligations [Line Items]
2025	2,309.6
2026	0.0
2027 and 2028	0.0
2029 and 2030	0.0
2031 and Later	0.0
Maximum Payout	2,309.6
Other unfunded commitments
Commitments And Guarantee Obligations [Line Items]
2025	340.8
2026	502.0
2027 and 2028	274.8
2029 and 2030	14.2
2031 and Later	0.0
Maximum Payout	1,131.8
Back-to-back committed sales contracts
Commitments And Guarantee Obligations [Line Items]
Maximum Payout	3,460.0
Forward Starting Resell
Commitments And Guarantee Obligations [Line Items]
Maximum Payout	$ 3,630.0