CONSOLIDATED T. ROWE PRICE INVESTMENT PRODUCTS. (Statement of Cash Flows) (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 1,640.7	$ 948.8
Net cash used in investing activities	2.4	(29.1)
Net cash provided by in financing activities	(1,311.1)	(501.5)
Effect of exchange rate changes on cash and cash equivalents of consolidated T. Rowe Price investment products	(7.4)	(0.4)
Net change in cash and cash equivalents during period	324.6	417.8
Cash and cash equivalents at beginning of period	1,858.3	1,495.3
Cash and cash equivalents at ending of period	2,182.9	1,913.1
Consolidation eliminations
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by in financing activities	26.2	146.9
Consolidated T. Rowe Price investment products
Condensed Cash Flow Statements, Captions [Line Items]
Cash and cash equivalents at beginning of period	76.5	70.1
Cash and cash equivalents at ending of period	124.8	110.7
Consolidated T. Rowe Price investment products \| Reportable entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(49.0)	(291.1)
Net cash used in investing activities	(9.2)	(5.1)
Net cash provided by in financing activities	113.9	337.2
Effect of exchange rate changes on cash and cash equivalents of consolidated T. Rowe Price investment products	(7.4)	(0.4)
Net change in cash and cash equivalents during period	48.3	40.6
Cash and cash equivalents at beginning of period	76.5	70.1
Cash and cash equivalents at ending of period	124.8	110.7
Voting interest entities \| Reportable entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0.8	(32.7)
Net cash used in investing activities	(9.2)	(5.1)
Net cash provided by in financing activities	9.9	34.5
Effect of exchange rate changes on cash and cash equivalents of consolidated T. Rowe Price investment products	0.0	0.0
Net change in cash and cash equivalents during period	1.5	(3.3)
Cash and cash equivalents at beginning of period	9.9	18.5
Cash and cash equivalents at ending of period	11.4	15.2
Variable interest entities \| Reportable entities
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(49.8)	(258.4)
Net cash used in investing activities	0.0	0.0
Net cash provided by in financing activities	104.0	302.7
Effect of exchange rate changes on cash and cash equivalents of consolidated T. Rowe Price investment products	(7.4)	(0.4)
Net change in cash and cash equivalents during period	46.8	43.9
Cash and cash equivalents at beginning of period	66.6	51.6
Cash and cash equivalents at ending of period	$ 113.4	$ 95.5

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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