Segment Information - Reconciliation of Revenues and Operating Measures from Segments to Consolidated (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended
		Sep. 30, 2025		Sep. 30, 2024	Sep. 30, 2025		Sep. 30, 2024
Segment Reporting Information [Line Items]
Revenues		$ 467.5		$ 451.9	$ 1,318.4		$ 1,337.7
Operating		(230.7)		(233.1)	(683.5)		(711.6)
Selling, General and Administrative Expense	[1]	(105.2)		(108.7)	(330.5)		(338.3)
Adjusted OIBDA		137.2		117.1	325.5		309.6
Operating income		89.9		71.3	160.0		314.4
Restructuring charges		(0.3)	[2]	0.0	(20.1)	[2]	0.0
Net (gain) loss on dispositions		(1.4)		(1.5)	(2.6)		153.6
Impairment charges		0.0		0.0	0.0		(17.9)
Depreciation		(22.4)		(18.6)	(69.6)		(55.5)
Amortization		(17.6)		(18.7)	(52.1)		(53.6)
Stock-based compensation		(5.6)		(7.0)	(21.1)		(21.8)
Interest expense, net		(37.0)		(37.1)	(109.5)		(119.6)
Loss on extinguishment of debt		(0.6)		0.0	(0.6)		(1.2)
Other income (loss), net		0.0		(0.1)	0.0		1.0
Income before benefit (provision) for income taxes and equity in earnings of investee companies		52.3		34.1	49.9		194.6
Benefit (provision) for income taxes		(1.2)		0.2	(1.9)		(10.4)
Equity in earnings of investee companies, net of tax		0.3		0.5	2.2		0.5
Net income before allocation to redeemable and non-redeemable noncontrolling interests		51.4		34.8	50.2		184.7
Net income attributable to redeemable and non-redeemable noncontrolling interests		0.1		0.2	0.0		0.5
Net income attributable to OUTFRONT Media Inc.		51.3		34.6	50.2		184.2
Stock-based compensation					23.3		21.8
Restructuring Charges
Segment Reporting Information [Line Items]
Restructuring charges		(0.3)
Stock-based compensation					2.2
Billboard Property Lease
Segment Reporting Information [Line Items]
Operating	[3]	(110.5)		(119.3)	(331.5)		(363.2)
Transit Franchise
Segment Reporting Information [Line Items]
Operating	[3]	(60.1)		(59.1)	(180.9)		(178.6)
Posting Maintenance And Other
Segment Reporting Information [Line Items]
Operating	[3]	(60.1)		(54.7)	(171.1)		(169.8)
Operating segments
Segment Reporting Information [Line Items]
Revenues		465.2		451.5	1,311.2		1,302.0
Operating	[3]	(228.8)		(232.7)	(677.8)		(689.5)
Selling, General and Administrative Expense	[1]	(81.4)		(85.3)	(252.0)		(256.7)
Adjusted OIBDA		155.0		133.5	381.4		355.8
Operating segments | Billboard Property Lease
Segment Reporting Information [Line Items]
Operating	[3]	(110.5)		(119.3)	(331.5)		(352.7)
Operating segments | Transit Franchise
Segment Reporting Information [Line Items]
Operating	[3]	(60.1)		(59.1)	(180.9)		(176.8)
Operating segments | Posting Maintenance And Other
Segment Reporting Information [Line Items]
Operating	[3]	(58.2)		(54.3)	(165.4)		(160.0)
Operating segments | Billboard Operating Segment
Segment Reporting Information [Line Items]
Revenues		352.8		360.6	1,014.8		1,034.7
Operating	[3]	(149.8)		(156.9)	(443.2)		(462.5)
Selling, General and Administrative Expense	[1]	(63.7)		(67.3)	(198.9)		(202.7)
Adjusted OIBDA		$ 139.3		$ 136.4	$ 372.7		$ 369.5
Segment Adjusted OIBDA Margin		39.50%		37.80%	36.70%		35.70%
Restructuring charges		$ (0.2)			$ (8.4)
Operating segments | Billboard Operating Segment | Billboard Property Lease
Segment Reporting Information [Line Items]
Operating	[3]	(110.5)		$ (119.3)	(331.5)		$ (352.7)
Operating segments | Billboard Operating Segment | Posting Maintenance And Other
Segment Reporting Information [Line Items]
Operating	[3]	(39.3)		(37.6)	(111.7)		(109.8)
Operating segments | Transit Operating Segment
Segment Reporting Information [Line Items]
Revenues		112.4		90.9	296.4		267.3
Operating	[3]	(79.0)		(75.8)	(234.6)		(227.0)
Selling, General and Administrative Expense	[1]	(17.7)		(18.0)	(53.1)		(54.0)
Adjusted OIBDA		$ 15.7		$ (2.9)	$ 8.7		$ (13.7)
Segment Adjusted OIBDA Margin		14.00%		(3.20%)	2.90%		(5.10%)
Restructuring charges		$ (0.1)			$ (3.7)
Operating segments | Transit Operating Segment | Transit Franchise
Segment Reporting Information [Line Items]
Operating	[3]	(60.1)		$ (59.1)	(180.9)		$ (176.8)
Operating segments | Transit Operating Segment | Posting Maintenance And Other
Segment Reporting Information [Line Items]
Operating	[3]	(18.9)		(16.7)	(53.7)		(50.2)
Corporate and Reconciling Items
Segment Reporting Information [Line Items]
Adjusted OIBDA		$ (17.8)		$ (16.4)	(55.9)		$ (46.2)
Restructuring charges					$ (8.0)

[1] Selling, general and administrative expenses includes, but is not limited to, compensation and benefits, including commissions, professional fees, office rent and travel and entertainment.

[2] In the three and nine months ended September 30, 2025, Restructuring charges associated with the Plan, consists of severance payments, employee benefits and related costs, and professional fees, and includes approximately $2.2 million in non-cash charges for stock-based compensation

[3] The significant expense categories and amounts align with the segment-level information that is regularly provided to the chief operating decision maker.