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		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator:
Net income	$ 543	$ 503	$ 1,430	$ 1,559
Denominator:
Basic: Weighted-average common shares outstanding	132.7	144.4	135.8	147.0
Effect of potentially dilutive nonqualified stock options and other share-based awards (in shares)	1.8	2.1	1.7	2.2
Diluted: Weighted-average common shares outstanding	134.5	146.5	137.5	149.2
Basic:
Net income (in dollars per share)	$ 4.09	$ 3.48	$ 10.53	$ 10.61
Diluted:
Net income (in dollars per share)	$ 4.04	$ 3.43	$ 10.40	$ 10.45
Effect of potentially dilutive nonqualified stock options and other share-based awards (in shares)			1.0	1.0