Investments (AFS contractual maturity) (Details) - Ameriprise Financial [Member] - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Amortized cost
Due within one year	$ 2,998
Due after one year through five years	4,845
Due after five years through 10 years	2,533
Due after 10 years	4,098
Total having single maturity dates	14,474
Amortized cost	33,614	$ 31,332
Fair value
Due within one year	3,013
Due after one year through five years	5,150
Due after five years through 10 years	2,814
Due after 10 years	5,424
Total having single maturity dates	16,401
Fair value	35,959	33,129
Residential mortgage backed securities [Member]
Amortized cost
Without single maturity dates	10,071
Amortized cost	10,071	9,954
Fair value
Without single maturity dates	10,258
Fair value	10,258	10,029
Commercial mortgage backed securities [Member]
Amortized cost
Without single maturity dates	6,016
Amortized cost	6,016	5,473
Fair value
Without single maturity dates	6,212
Fair value	6,212	5,563
Asset backed securities [Member]
Amortized cost
Without single maturity dates	3,053
Amortized cost	3,053	1,968
Fair value
Without single maturity dates	3,088
Fair value	$ 3,088	$ 2,006