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
	Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net income	$ 2,036	$ 395
Denominator:
Basic: Weighted-average common shares outstanding	126.4	138.8
Effect of potentially dilutive nonqualified stock options and other share-based awards (in shares)	1.8	1.3
Diluted: Weighted-average common shares outstanding	128.2	140.1
Basic:
Net income (in dollars per share)	$ 16.11	$ 2.85
Diluted:
Net income (in dollars per share)	$ 15.88	$ 2.82
Effect of potentially dilutive nonqualified stock options and other share-based awards (in shares)	4.5	4.4