Earnings per Share Attributable to Ameriprise Financial, Inc. Common Shareholders (Basic & Diluted) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Net income	$ 492	$ 462	$ 887	$ 1,056
Denominator:
Basic: Weighted-average common shares outstanding	136.1	147.0	137.4	148.2
Effect of potentially dilutive nonqualified stock options and other share-based awards (in shares)	1.9	2.0	1.7	2.3
Diluted: Weighted-average common shares outstanding	138.0	149.0	139.1	150.5
Basic:
Net income (in dollars per share)	$ 3.61	$ 3.14	$ 6.46	$ 7.13
Diluted:
Net income (in dollars per share)	$ 3.57	$ 3.10	$ 6.38	$ 7.02
Effect of potentially dilutive nonqualified stock options and other share-based awards (in shares)			1.0	1.1