Compensation Plans - Senior Executive Compensation Plan (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended
Dec. 31, 2023	Aug. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, outstanding (in shares)		5.1
Potential maximum increase to common shares outstanding from outstanding awards (in shares)		19.4
Restricted stock with future service required
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non option equity, outstanding (in shares)		2.3
RSUs with future service required
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non option equity, outstanding (in shares)		5.1
RSU with no future service required
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non option equity, outstanding (in shares)		9.2
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value	$ 11.7
Vesting period (in years)	3 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value	$ 8.8
Target level of ROTE	10.00%
ROTE threshold level	7.50%
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target level of ROTE	15.00%
Percentage of target PSUs	150.00%
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target level of ROTE	7.50%
Percentage of target PSUs	75.00%

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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