Leases (Tables)

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

Components of Lease Costs

Operating lease cost was $16.8 million, $15.7 million and $15.3 for the years ended December 31, 2023 , December 31, 2022 and December 31, 2021, respectively. The components of lease costs are as follows:

	December 31,
(millions of dollars)	2023			2022			2021
Operating lease cost		$	16.7		$	15.6	$	15.2
Short-term lease cost			0.1			0.1		0.1
Total		$	16.8		$	15.7	$	15.3

Supplemental Cash Flow Information and Non-cash Activity Related to Operating Leases

Supplemental cash flow information and non-cash activity related to our leases are as follows:

(millions of dollars)	December 31, 2023
Operating cash flows information:
Cash paid for amounts included in the measurement of lease liabilities	$	16.8
Non-cash activity:
Right-of-use assets obtained in the exchange for operating lease liabilities	$	10.0

Weighted Average Remaining Lease Term and Discount Rates

Weighted average remaining lease term, and weighted average discount rates related to the Company’s leases were as follows:

Weighted-average remaining operating lease term (in years)	5.55
Weighted-average operating leases discount rate	5.1	%

Outstanding Lease Assets and Liabilities

The following table summarizes the Company’s outstanding lease assets and liabilities and their classification on the Consolidated Balance Sheet:

		December 31,
(millions of dollars)	Balance Sheet Classification	2023		2022
Right-of-use-asset	Other assets and deferred charges	$	44.1	$	49.1
Lease liability - current	Other current liabilities		13.5		13.5
Lease liability - non-current	Other non-current liabilities		37.9		43.9

Future Minimum Lease Payments

Future minimum lease payments under the Company’s leases as of December 31, 2023 were as follows:

(millions of dollars)	December 31, 2023
2024	$	15.7
2025		12.5
2026		10.6
2027		7.3
2028		5.9
Thereafter		7.6
Total future minimum lease payments		59.6
Less imputed interest		(8.2	)
Total	$	51.4