Earnings Per Common Share - Calculation Of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Net income attributable to Invesco Ltd.	$ 368.3	$ 40.5	$ 636.1	$ 122.0
Weighted average shares outstanding - basic (in shares)	462.8	460.1	462.2	457.9
Dilutive effect of non-participating common share-based awards (in shares)	3.4	3.0	3.1	3.1
Weighted average shares outstanding - diluted (in shares)	466.2	463.1	465.3	461.0
Earnings per common share:
- basic (usd per share)	$ 0.80	$ 0.09	$ 1.38	$ 0.27
- diluted (usd per share)	$ 0.79	$ 0.09	$ 1.37	$ 0.26