
	December 31,
	2023		2022
Components of Deferred Tax Assets and Liabilities	($ in millions)
Deferred Tax Assets
Pension and postretirement benefits	$	42.4	$	42.9
Environmental reserves	38.3		37.4
Asset retirement obligations	16.6		13.9
Accrued liabilities	46.1		47.4
Lease liabilities	88.1		91.4
Tax credits	47.3		37.4
Net operating losses (NOL)	54.1		23.2

Other miscellaneous items	3.0		2.7
Total deferred tax assets	335.9		296.3
Valuation allowance	(99.5)		(76.4)
Net deferred tax assets	236.4		219.9

Deferred Tax Liabilities
Property, plant and equipment	439.5		481.7
Right-of-use lease assets	86.5		89.8
Intangible amortization	76.9		68.7
Inventory and prepaids	5.5		12.1

Taxes on unremitted earnings	16.8		12.0
Other miscellaneous items	—		2.4
Total deferred tax liabilities	625.2		666.7

Net deferred income tax liability	$	(388.8)	$	(446.8)

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Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years.

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Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.

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