Fair Values of Assets and Liabilities Fair Value of Assets & Liabilities (Non-Recurring) (Details) - VIEs, not primary beneficiary [Member] - RiverSource Tax Advantaged Investments Inc [Member] - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Assets and liabilities measured at fair value
Affordable housing partnership, amount	$ 235	$ 270
Nonrecurring basis [Member] | Level 3 [Member]
Assets and liabilities measured at fair value
Affordable housing partnership, amount	$ 120	$ 158