Earnings Per Share (Calculation Of Earnings Per Share) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Earnings Per Share [Abstract]
Income from continuing operations, net of taxes	$ 1,004.5	$ 918.3	$ 569.2
Net (income)/loss attributable to noncontrolling interests in consolidated entities	(13.0)	(42.5)	89.8
Income from continuing operations attributable to Invesco Ltd. for basic and diluted EPS calculations	991.5	875.8	659.0
Income/(loss) from discontinued operations, net of taxes	(3.4)	64.5	18.1
Net income attributable to common shareholders	$ 988.1us-gaap_NetIncomeLoss	$ 940.3us-gaap_NetIncomeLoss	$ 677.1us-gaap_NetIncomeLoss
Weighted average shares outstanding - basic (in shares)	435.0	447.5	452.3
Dilutive effect on share-based awards (in shares)	0.6	1.0	1.5
Weighted average shares outstanding - diluted (in shares)	435.6	448.5	453.8
Basic earnings per share:
Earnings per share from continuing operations (usd per share)	$ 2.28	$ 1.96	$ 1.46
Earnings per share from discontinued operations (usd per share)	$ (0.01)	$ 0.14	$ 0.04
Basic earnings per share (usd per share)	$ 2.27us-gaap_EarningsPerShareBasic	$ 2.10us-gaap_EarningsPerShareBasic	$ 1.50us-gaap_EarningsPerShareBasic
Diluted earnings per share:
Earnings per share from continuing operations (usd per share)	$ 2.28	$ 1.95	$ 1.45
Earnings per share from discontinued operations (usd per share)	$ (0.01)	$ 0.14	$ 0.04
Diluted earnings per share (usd per share)	$ 2.27us-gaap_EarningsPerShareDiluted	$ 2.10us-gaap_EarningsPerShareDiluted	$ 1.49us-gaap_EarningsPerShareDiluted

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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