Financial Instruments and Fair Value Disclosures - (Mortgage Servicing Rights Unobservable Inputs) (Details) - Financial Services - Level 3	Feb. 28, 2021
Mortgage prepayment rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Unobservable inputs for valuation of mortgage servicing rights	0.12
Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Unobservable inputs for valuation of mortgage servicing rights	0.14
Delinquency rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Unobservable inputs for valuation of mortgage servicing rights	0.03