CONSOLIDATED INVESTMENT PRODUCTS - Net Assets (Details) - USD ($) $ in Millions	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	$ 3,634.8		$ 2,649.8
Investments	3,417.4		3,000.5
Other assets	690.6		685.6
Total assets	14,730.4		13,472.0
Liabilities	2,761.0		2,021.9
Attributable to redeemable non-controlling interests	984.9	$ 1,099.1	944.0	$ 763.4	$ 689.0	$ 594.1
Consolidated T. Rowe Price investment products
Condensed Balance Sheet Statements, Captions [Line Items]
Attributable to T. Rowe Price Group, Inc.	770.1		1,037.9
Attributable to redeemable non-controlling interests	984.9		944.0
Voting interest entities
Condensed Balance Sheet Statements, Captions [Line Items]
Attributable to T. Rowe Price Group, Inc.	132.4		348.5
Attributable to redeemable non-controlling interests	44.5		124.0
Variable interest entities
Condensed Balance Sheet Statements, Captions [Line Items]
Total assets	455.9		467.7
Liabilities	0.8		0.4
Attributable to T. Rowe Price Group, Inc.	637.7		689.4
Attributable to redeemable non-controlling interests	940.4		820.0
Reportable entities | Consolidated T. Rowe Price investment products
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	49.1		63.1
Investments	1,705.4		1,936.2
Other assets	23.2		44.7
Total assets	1,777.7		2,044.0
Liabilities	22.7		62.1
Net assets	1,755.0		1,981.9
Reportable entities | Consolidated T. Rowe Price investment products | T. Rowe Price investment products
Condensed Balance Sheet Statements, Captions [Line Items]
Investments	41.5		9.3
Reportable entities | Consolidated T. Rowe Price investment products | Money Market Funds | T. Rowe Price investment products
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	1.4		4.9
Reportable entities | Voting interest entities
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	1.9		7.2
Investments	174.3		470.8
Other assets	1.7		10.4
Total assets	177.9		488.4
Liabilities	1.0		15.9
Net assets	176.9		472.5
Reportable entities | Variable interest entities
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	47.2		55.9
Investments	1,531.1		1,465.4
Other assets	21.5		34.3
Total assets	1,599.8		1,555.6
Liabilities	21.7		46.2
Net assets	$ 1,578.1		$ 1,509.4