Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income Taxes

Schedule of income tax (benefit) expense (in thousands)

	2017		2016		2015
Current income tax expense	$	5,407	$	5,087	$	4,822
Deferred income tax (benefit) expense		(7,612)		777		(227)
Income tax (benefit) expense	$	(2,205)	$	5,864	$	4,595

Schedule of reconciliation of income taxes computed at the federal statutory rate to income tax expense (in thousands)

	2017				2016				2015
			Percent of				Percent of				Percent of
			Pretax				Pretax				Pretax
	Amount		Income		Amount		Income		Amount		Income
Income taxes computed at the federal statutory rate	$	8,730	35.0	%	$	8,266	35.0	%	$	6,118	35.0	%
(Reduction) increase in taxes resulting from:
Benefit of reduced federal income tax rates		(7,447)	(29.9)			—	—			—	—
Statutory depletion in excess of cost depletion		(2,004)	(8.0)			(1,854)	(7.9)			(1,708)	(9.8)
Research & development tax credit		(1,433)	(5.7)			(167)	(0.7)			—	—
Manufacturing deduction		(674)	(2.7)			(666)	(2.8)			(548)	(3.1)
State income taxes, net of federal income tax benefit		235	0.9			202	0.9			309	1.8
Other		388	1.6			83	0.3			424	2.4
Income tax (benefit) expense	$	(2,205)	(8.8)	%	$	5,864	24.8	%	$	4,595	26.3	%

Summary of the Company's deferred tax liabilities and assets (in thousands)

	December 31,		December 31,
	2017		2016
Deferred tax liabilities
Lime and limestone property, plant and equipment	$	11,023	$	17,907
Fair value liability of foreign exchange hedges		26		—
Natural gas interests drilling costs and equipment		1,622		2,811
		12,671		20,718
Deferred tax assets
Alternative minimum tax credit carry forwards		—		296
Fair value liability of foreign exchange hedges		—		129
Other		297		461
		297		886
Deferred tax liabilities, net	$	12,374	$	19,832

Current income taxes are classified on the Company’s Consolidated Balance Sheets as follows:

Prepaid expenses and other current assets $ 1,394 $ 75