The categories of assets and liabilities that have resulted in differences in the timing of the recognition of income and expense at December 31, 2015 and 2014 were as follows:



(In millions)	2015			2014
Deferred income tax assets
Pensions	$	281.0		$	251.8
Postretirement benefits other than pensions	144.7			169.0
Federal and state net operating loss tax carryovers	228.1			122.7
Federal and state tax credits	52.2			53.6
Deferred compensation and other benefit plans	25.9			25.6
Self insurance reserves	10.8			10.1
Other items	85.2			79.1
Gross deferred income tax assets	827.9			711.9
Valuation allowance for deferred tax assets	(105.1		)	(34.4		)
Total deferred income tax assets	722.8			677.5
Deferred income tax liabilities
Bases of property, plant and equipment	664.1			579.5
Inventory valuation	62.2			111.7
Bases of amortizable intangible assets	25.4			75.5
Other items	46.7			53.9
Total deferred tax liabilities	798.4			820.6
Net deferred tax liability	$	(75.6	)	$	(143.1	)

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