CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Common shares, shares authorized	1,250,000,000	1,250,000,000
Equity:
Common shares, par value (in dollars per share)	$ 0.01	$ 0.01
Common shares, shares authorized	1,250,000,000	1,250,000,000
Common shares, shares issued	334,347,693	332,390,132
Treasury shares	221,950,106	215,624,519
Ameriprise Financial
Assets
Investments, allowance for credit losses	$ 19	$ 52
Receivables, allowance for credit loss	$ 52	$ 49