Reportable Segments (Details) $ in Millions	3 Months Ended		6 Months Ended
Reportable Segments (Details) $ in Millions	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) segments	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segments			2
Operating Revenues	$ 534.0	$ 477.5	$ 1,152.6	$ 988.0
Costs associated with service revenues	7.2	6.6	15.2	13.8
Costs associated with product sales	95.6	78.9	218.5	142.7
Operation and maintenance	75.0	79.1	133.2	138.0
Administrative and general	46.5	42.9	94.8	92.2
Taxes other than income taxes	33.3	28.7	65.6	60.4
Loss (gain) on sale of assets, impairments and other	0.1	0.0	(0.9)	(7.7)
Miscellaneous other income, net	0.6	0.9	1.8	3.9
Segment EBITDA	276.9	242.2	628.0	552.5
Depreciation and amortization	118.9	106.5	224.4	212.0
Interest expense	39.8	46.9	79.3	90.2
Interest income	(3.0)	(8.8)	(4.0)	(12.5)
Consolidated income before income taxes	121.2	97.6	328.3	262.8
Total Assets	9,980.8		9,980.8		$ 9,779.4
Capital expenditures			121.9	196.4
Operating Segments
Segment Reporting Information [Line Items]
Revenue From External Customers	534.0	477.5	1,152.6	988.0
Intrasegment revenues	12.9	12.3	25.9	24.7
Operating Revenues	546.9	489.8	1,178.5	1,012.7
Total Assets	9,029.9		9,029.9		9,118.8
Intersegment Eliminations
Segment Reporting Information [Line Items]
Intrasegment revenues	12.9	12.3	25.9	24.7
Operating Revenues	(12.9)	(12.3)	(25.9)	(24.7)
Natural Gas Reportable Segment
Segment Reporting Information [Line Items]
Revenue From External Customers	362.4	318.0	773.1	691.3
Natural Gas Reportable Segment \| Operating Segments
Segment Reporting Information [Line Items]
Intrasegment revenues	12.9	12.3	25.9	24.7
Operating Revenues	375.3	330.3	799.0	716.0
Costs associated with service revenues	11.5	9.8	23.5	19.8
Costs associated with product sales	0.0	0.0	0.0	0.0
Operation and maintenance	62.8	62.4	110.6	108.9
Administrative and general	44.0	40.9	90.5	88.1
Taxes other than income taxes	30.3	25.3	59.2	53.6
Loss (gain) on sale of assets, impairments and other	0.1		(0.9)	(7.7)
Miscellaneous other income, net	(0.7)	(0.9)	(1.8)	(3.8)
Segment EBITDA	227.3	192.8	517.9	457.1
Total Assets	7,528.8		7,528.8		7,490.1
Capital expenditures			104.7	166.2
Natural Gas Liquids Reportable Segment
Segment Reporting Information [Line Items]
Revenue From External Customers	171.6	159.5	379.5	296.7
Natural Gas Liquids Reportable Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating Revenues	171.6	159.5	379.5	296.7
Costs associated with service revenues	4.3	4.6	8.6	9.3
Costs associated with product sales	95.6	78.9	218.5	142.7
Operation and maintenance	12.2	16.7	22.6	29.1
Administrative and general	6.8	6.5	13.3	13.5
Taxes other than income taxes	3.0	3.4	6.4	6.8
Loss (gain) on sale of assets, impairments and other	0.0		0.0	0.0
Miscellaneous other income, net	0.1	0.0	0.0	(0.1)
Segment EBITDA	49.6	$ 49.4	110.1	95.4
Total Assets	$ 1,501.1		1,501.1		$ 1,628.7
Capital expenditures			$ 17.2	$ 30.2

Boardwalk Pipeline Partners, LP 10-Q