Income Taxes (Tables)

12 Months Ended

Aug. 31, 2017

Aug. 31, 2016

Schedule of components of income tax expense (benefit)

The provision for income taxes for the years ended August 31, 2017, 2016, and 2015 is as follows:



	2017			2016			2015
	(Dollars in thousands)
Current:
Federal	$	(1,767	)	$	3,386		$	(47,695	)
State	2,695			3,972			3,891
Foreign	(7,088		)	12,729			1,335
	(6,160		)	20,087			(42,469		)
Deferred:
Federal	(162,223		)	(30,758		)	29,348
State	(15,977		)	8,512			(2,799		)
Foreign	2,285			(1,932		)	3,755
	(175,915		)	(24,178		)	30,304
Total	$	(182,075	)	$	(4,091	)	$	(12,165	)

Schedule of deferred tax assets and liabilities

Deferred tax assets and liabilities as of August 31, 2017, and 2016, are as follows:



	2017			2016
	(Dollars in thousands)
Deferred tax assets:
Accrued expenses	$	226,964		$	87,251
Postretirement health care and deferred compensation	82,682			111,983
Tax credit carryforwards	166,213			143,252
Loss carryforwards	169,724			155,966
Nonqualified equity	152,835			30,168
Other	55,119			30,627
Deferred tax assets valuation	(284,716		)	(194,277		)
Total deferred tax assets	568,821			364,970
Deferred tax liabilities:
Pension	31,050			26,516
Investments	129,985			107,716
Major maintenance	2,115			4,970
Property, plant and equipment	712,195			681,160
Other	25,964			29,905
Total deferred tax liabilities	901,309			850,267
Net deferred tax liabilities	$	332,488		$	485,297

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, 2017, 2016, and 2015 is as follows:



	2017		2016		2015
Statutory federal income tax rate	35.0	%	35.0	%	35.0	%
State and local income taxes, net of federal income tax benefit	24.7		0.4		(0.5	)
Patronage earnings	192.0		(23.2	)	(29.0	)
Domestic production activities deduction	64.7		(13.2	)	(5.6	)
Export activities at rates other than the U.S. statutory rate	145.3		1.5		(0.2	)
Valuation allowance	(182.3	)	19.6		(0.1	)
Tax credits	45.8		(11.8	)	(0.8	)
Crack spread contingency	9.6		(5.0	)	(1.7	)
Other	(2.9	)	(4.3	)	1.3
Effective tax rate	331.9	%	(1.0	)%	(1.6	)%

Schedule of unrecognized tax benefits roll forward



	2017		2016			2015
	(Dollars in thousands)
Balance at beginning of period	$	37,105	$	72,181		$	72,181
Additions attributable to current year tax positions	725		1,387			—
Reductions attributable to prior year tax positions	—		(36,463		)	—
Balance at end of period	$	37,830	$	37,105		$	72,181