Benefits and Pension Plans (Tables)

12 Months Ended

Aug. 31, 2017

Benefits and pension plans

Schedule of the status of the Company's pension plans

	Year Ended August 31,
	2017		2016		2015
Change in benefit obligation
Projected benefit obligation at beginning of year	$	23,636	$	20,401	$	18,279
Service cost		288		295		349
Interest cost		681		728		678
Assumption change		—		—		40
Actuarial (gain) loss		(533)		2,636		1,762
Settlements		(313)		(376)		(619)
Benefits paid		(1,086)		(48)		(89)
Projected benefit obligation at end of year	$	22,673	$	23,636	$	20,401
Change in plan assets
Fair value of plan assets at beginning of year	$	8,440	$	8,120	$	8,818
Actual return on plan assets		757		422		(296)
Employer contribution		1,205		322		306
Settlements		(313)		(376)		(619)
Benefits paid		(1,086)		(48)		(89)
Fair value of plan assets at end of year	$	9,003	$	8,440	$	8,120
Funded status at end of year	$	(13,670)	$	(15,196)	$	(12,281)

	Year Ended August 31,
	2017		2016		2015
Amounts recognized in consolidated balance sheets
Noncurrent assets	$	566	$	382	$	634
Current liabilities		(1,570)		(15)		(14)
Noncurrent liabilities		(12,666)		(15,563)		(12,901)
Net amount recognized in consolidated balance sheets	$	(13,670)	$	(15,196)	$	(12,281)
Actuarial present value of benefit obligation and funded status
Accumulated benefit obligations	$	21,007	$	22,023	$	18,784
Projected benefit obligations	$	22,673	$	23,636	$	20,401
Plan assets at fair value	$	9,003	$	8,440	$	8,120
Amounts recognized in accumulated other comprehensive income
Prior service cost	$	54	$	57	$	61
Net actuarial loss		9,890		11,561		9,417
Adjustment to pre-tax accumulated other comprehensive income	$	9,944	$	11,618	$	9,478

	Year Ended August 31,
	2017		2016		2015
Other changes in plan assets and benefit obligations recognized in other comprehensive income
Net loss	$	1,277	$	511	$	4,371
Amortization of loss		(895)		(574)		(667)
Supplemental plan assumption change		(2,038)		2,219		(1,667)
Amortization of prior service cost		(3)		(3)		(3)
Effect of settlement on accumulated other comprehensive income		(14)		(13)		(188)
Total recognized in other comprehensive income		(1,673)		2,140		1,846
Net periodic pension cost		1,353		1,097		1,280
Total recognized in net periodic pension cost and other comprehensive income	$	(320)	$	3,237	$	3,126
Estimated amounts that will be amortized from accumulated comprehensive income over the next fiscal year
Prior service cost	$	3	$	3	$	3
Net actuarial loss		485		895		574

Prior service cost arose from the amendment of the plan’s benefit schedules to comply with the Tax Reform Act of 1986 and adoption of the unfunded supplemental pension plan.

Components of net periodic pension cost for the fiscal years ended August 31, 2017, 2016 and 2015 included the following:

	2017		2016		2015
Components of net periodic benefit cost
Service cost	$	288	$	295	$	349
Interest cost		681		728		678
Expected return on plan assets		(528)		(516)		(605)
Amortization of prior service cost		3		3		3
Amortization of accumulated loss		895		574		667
Settlement and curtailment loss		14		13		188
Net periodic benefit cost	$	1,353	$	1,097	$	1,280

Weighted average assumptions used to determine benefit obligations as of August 31, 2017, 2016 and 2015 are as follows:

	2017		2016		2015
Discount rate
Qualified plan	3.30	%	2.90	%	4.16	%
Supplemental plan	2.73	%	2.97	%	3.22	%
NEPTCO plan	2.95	%	2.55	%	4.30	%
Rate of compensation increase
Qualified and Supplemental plan	3.50	%	3.50	%	3.50	%
NEPTCO plan	—	%	—	%	—	%

Weighted average assumptions used to determine net periodic benefit cost for the years ended August 31, 2017, 2016 and 2015 are as follows:

	2017		2016		2015
Discount rate
Qualified plan	2.90	%	4.16	%	3.83	%
Supplemental plan	2.97	%	3.22	%	3.01	%
NEPTCO plan	2.55	%	4.30	%	4.06	%
Expected long-term return on plan assets
Qualified plan	6.50	%	6.50	%	7.00	%
Supplemental plan	—	%	—	%	—	%
NEPTCO plan	6.50	%	6.50	%	7.00	%
Rate of compensation increase
Qualified and Supplemental plan	3.50	%	3.50	%	3.50	%
NEPTCO plan	—	%	—	%	—	%

Schedule of components of net periodic benefit cost

	2017		2016		2015
Components of net periodic benefit cost
Service cost	$	288	$	295	$	349
Interest cost		681		728		678
Expected return on plan assets		(528)		(516)		(605)
Amortization of prior service cost		3		3		3
Amortization of accumulated loss		895		574		667
Settlement and curtailment loss		14		13		188
Net periodic benefit cost	$	1,353	$	1,097	$	1,280

Schedule of weighted-average assumptions used to determine benefit obligations

	2017		2016		2015
Discount rate
Qualified plan	3.30	%	2.90	%	4.16	%
Supplemental plan	2.73	%	2.97	%	3.22	%
NEPTCO plan	2.95	%	2.55	%	4.30	%
Rate of compensation increase
Qualified and Supplemental plan	3.50	%	3.50	%	3.50	%
NEPTCO plan	—	%	—	%	—	%

Schedule of weighted-average assumptions used to determine net periodic benefit cost

	2017		2016		2015
Discount rate
Qualified plan	2.90	%	4.16	%	3.83	%
Supplemental plan	2.97	%	3.22	%	3.01	%
NEPTCO plan	2.55	%	4.30	%	4.06	%
Expected long-term return on plan assets
Qualified plan	6.50	%	6.50	%	7.00	%
Supplemental plan	—	%	—	%	—	%
NEPTCO plan	6.50	%	6.50	%	7.00	%
Rate of compensation increase
Qualified and Supplemental plan	3.50	%	3.50	%	3.50	%
NEPTCO plan	—	%	—	%	—	%

Schedule of pension plans' assets by asset category

			Fair value measurements at								Fair value measurements at
			August 31, 2017								August 31, 2016
					Significant								Significant
			Quoted prices		other		Significant				Quoted prices		other		Significant
			in active		observable		unobservable				in active		observable		unobservable
	August 31,		markets		inputs		inputs		August 31,		markets		inputs		inputs
	2017		(Level 1)		(Level 2)		(Level 3)		2016		(Level 1)		(Level 2)		(Level 3)
Asset Category
Equity securities	$	3,589	$	3,589	$	—	$	—	$	3,866	$	3,866	$	—	$	—
Debt securities		5,336		5,336		—		—		4,499		4,499		—		—
Other		78		78		—		—		75		75		—		—
Total	$	9,003	$	9,003	$	—	$	—	$	8,440	$	8,440	$	—	$	—

Schedule of pension benefit payments (which include expected future service) expected to be paid

Year ending August 31,	Pension Benefits
2018	$	2,395
2019		1,970
2020		1,998
2021		1,916
2022		2,299
2023-2027	$	9,345

Qualified Plan

Benefits and pension plans

Schedule of target allocation and weighted-average asset allocations

	Target
	Allocation		Percentage of Plan Assets as of August 31,
Asset Category	Range		2017		2016		2015
Equity securities	10-80	%	39	%	46	%	44	%
Debt securities	20-70	%	61	%	54	%	56	%
Other	0-100	%	—	%	—	%	—	%
Total	100	%	100	%	100	%	100	%

Neptco plan

Benefits and pension plans

Schedule of target allocation and weighted-average asset allocations

	Target
	Allocation		Percentage of Plan Assets as of August 31,
Asset Category	Range		2017		2016		2015
Equity securities	10-80	%	43	%	43	%	41	%
Debt securities	20-70	%	51	%	50	%	53	%
Other	0-100	%	6	%	7	%	6	%
Total	100	%	100	%	100	%	100	%