December 31,
(dollars in thousands)	2019				2018
Deferred income tax assets:
Pension	$	7,510			$	9,722
Non-pension post-retirement benefits		12,271				11,712
Other accrued liabilities		22,486				16,477
Receivables		2,544				1,994
Operating lease liabilities		15,068				—
Net operating loss and charitable contribution carryforwards		11,333		(1)		14,143
Tax credits		11,432		(2)		13,373
Total deferred income tax assets		82,644		(3)		67,421
Valuation allowances		(26,963	)			(22,068	)
Net deferred income tax assets		55,681				45,353

Deferred income tax liabilities:
Property, plant and equipment		13,213				15,332
Inventories		1,587				1,699
Operating lease right-of-use assets		14,009				—
Intangibles and other		4,229				4,987
Total deferred income tax liabilities		33,038				22,018
Net deferred income tax asset	$	22,643			$	23,335

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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