Income Taxes (Tables)

12 Months Ended

Aug. 31, 2016

Aug. 31, 2015

Schedule of components of income tax expense (benefit)

The provision for income taxes for the years ended August 31, 2016, 2015 and 2014 is as follows:



	2016			2015			2014
	(Dollars in thousands)
Current:
Federal	$	3,386		$	(47,695	)	$	38,653
State	3,972			3,891			31,203
Foreign	12,729			1,335			2,837
	20,087			(42,469		)	72,693
Deferred:
Federal	(30,758		)	29,348			(23,444		)
State	8,512			(2,799		)	(1,893		)
Foreign	(1,932		)	3,755			940
	(24,178		)	30,304			(24,397		)
Total	$	(4,091	)	$	(12,165	)	$	48,296

Schedule of deferred tax assets and liabilities

Deferred tax assets and liabilities as of August 31, 2016 and 2015 are as follows:



	2016			2015
	(Dollars in thousands)
Deferred tax assets:
Accrued expenses	$	87,251		$	96,270
Postretirement health care and deferred compensation	111,983			89,934
Tax credit carryforwards	143,252			109,756
Loss carryforwards	155,966			85,860
Other	64,669			68,625
Deferred tax assets valuation	(194,277		)	(98,024		)
Total deferred tax assets	368,844			352,421
Deferred tax liabilities:
Pension	26,516			20,732
Investments	109,610			98,291
Major maintenance	4,970			36,135
Property, plant and equipment	679,266			654,057
Other	33,779			25,836
Total deferred tax liabilities	854,141			835,051
Net deferred tax liabilities	$	485,297		$	482,630

Schedule of effective income tax rate reconciliation

The reconciliation of the statutory federal income tax rates to the effective tax rates for the years ended August 31, 2016, 2015 and 2014 is as follows:



	2016		2015		2014
Statutory federal income tax rate	35.0	%	35.0	%	35.0	%
State and local income taxes, net of federal income tax benefit	0.4		(0.5	)	1.6
Patronage earnings	(23.2	)	(29.0	)	(20.5	)
Domestic production activities deduction	(13.2	)	(5.6	)	(10.0	)
Export activities at rates other than the U.S. statutory rate	1.5		(0.2	)	1.2
Valuation allowance	19.6		(0.1	)	1.7
Tax credits	(11.8	)	(0.8	)	(3.1	)
Crack spread contingency	(5.0	)	(1.7	)	(0.6	)
Other	(4.3	)	1.3		(1.0	)
Effective tax rate	(1.0	)%	(1.6	)%	4.3	%

Schedule of unrecognized tax benefits roll forward

econciliation of the gross beginning and ending amounts of unrecognized tax benefits for the periods presented follows:



	2016			2015		2014
	(Dollars in thousands)
Balance at beginning of period	$	72,181		$	72,181	$	67,271
Additions attributable to current year tax positions	1,387			—		—
Additions attributable to prior year tax positions	—			—		35,718
Reductions attributable to prior year tax positions	(36,463		)	—		(9,867		)
Reductions attributable to statute expiration	—			—		(20,941		)
Balance at end of period	$	37,105		$	72,181	$	72,181