Business Segment Information (Schedule of Total Assets and Total Growth and Maintenance Capital Expenditures by Reportable Segment) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Segment Reporting Information [Line Items]
Assets	$ 5,412,757		$ 4,860,703
Capital Expenditures	$ 67,622	$ 93,817
Costs incurred, percentage	1	1
Operating Segments
Segment Reporting Information [Line Items]
Assets	$ 4,179,517		4,827,040
Capital Expenditures	66,042	$ 93,163
Operating Segments \| Offshore pipeline transportation
Segment Reporting Information [Line Items]
Assets	2,654,973		2,755,595
Capital Expenditures	19,077	59,136
Operating Segments \| Marine transportation
Segment Reporting Information [Line Items]
Assets	582,248		618,474
Capital Expenditures	39,401	29,452
Operating Segments \| Onshore transportation and services
Segment Reporting Information [Line Items]
Assets	942,296		1,452,971
Capital Expenditures	7,564	4,575
Other assets(1)
Segment Reporting Information [Line Items]
Assets	1,233,240		$ 33,663
Other
Segment Reporting Information [Line Items]
Capital Expenditures	$ 1,580	$ 654