RETIREMENT PLANS (Tables)

12 Months Ended

Sep. 30, 2015

Compensation and Retirement Disclosure [Abstract]

Schedule of changes in benefit obligations, fair values of plan assets and reconciliations of the funded status of the retirement plans

The following tables detail the changes in benefit obligations, fair values of plan assets and reconciliations of the funded status of the retirement plans:

	Pension						SERP						Postretirement Medical
	September 30,
	2015			2014			2015			2014			2015			2014
Change in Projected Benefit Obligation:
Benefit obligation at beginning of year	$	8,299,000		$	6,858,000		$	1,767,000		$	1,322,000		$	1,227,000		$	1,073,000
Service cost	256,000			156,000			62,000			47,000			—			12,000
Interest cost	356,000			322,000			77,000			67,000			52,000			54,000
Actuarial loss	110,000			1,186,000			—			337,000			40,000			88,000
Benefits paid	(326,000		)	(213,000		)	(6,000		)	(6,000		)	—			—
Administrative expenses paid	(12,000		)	(10,000		)	—			—			—			—
Benefit obligation at end of year	8,683,000			8,299,000			1,900,000			1,767,000			1,319,000			1,227,000
Change in Plan Assets:
Fair value of plan assets at beginning of year	7,022,000			6,111,000			—			—			—			—
Actual return on plan assets	(446,000		)	784,000			—			—			—			—
Employer contributions	250,000			350,000			6,000			6,000			—			—
Benefits paid	(326,000		)	(213,000		)	(6,000		)	(6,000		)	—			—
Administrative expenses paid	(12,000		)	(10,000		)	—			—			—			—
Fair value of plan assets at end of year	6,488,000			7,022,000			—			—			—			—
Funded status	$	(2,195,000	)	$	(1,277,000	)	$	(1,900,000	)	$	(1,767,000	)	$	(1,319,000	)	$	(1,227,000	)

Schedule of amounts recognized in the consolidated balance sheets

	Pension						SERP						Postretirement Medical
	September 30,
	2015			2014			2015			2014			2015			2014
Amounts recognized in the Consolidated Balance Sheets:
Current liabilities	$	—		$	—		$	(5,000	)	$	(5,000	)	$	—		$	—
Noncurrent liabilities	(2,195,000		)	(1,277,000		)	(1,895,000		)	(1,762,000		)	(1,319,000		)	(1,227,000		)
Net amount	$	(2,195,000	)	$	(1,277,000	)	$	(1,900,000	)	$	(1,767,000	)	$	(1,319,000	)	$	(1,227,000	)
Amounts recognized in accumulated other comprehensive (loss) income:
Net actuarial loss (gain)	$	3,038,000		$	2,068,000		$	506,000		$	530,000		$	(110,000	)	$	(155,000	)
Prior service cost (credit)	77,000			81,000			(76,000		)	(80,000		)	—			—
Accumulated other comprehensive loss (income)	$	3,115,000		$	2,149,000		$	430,000		$	450,000		$	(110,000	)	$	(155,000	)

Schedule of amounts recognized in accumulated other comprehensive (loss) income

	Pension						SERP						Postretirement Medical
	September 30,
	2015			2014			2015			2014			2015			2014
Amounts recognized in the Consolidated Balance Sheets:
Current liabilities	$	—		$	—		$	(5,000	)	$	(5,000	)	$	—		$	—
Noncurrent liabilities	(2,195,000		)	(1,277,000		)	(1,895,000		)	(1,762,000		)	(1,319,000		)	(1,227,000		)
Net amount	$	(2,195,000	)	$	(1,277,000	)	$	(1,900,000	)	$	(1,767,000	)	$	(1,319,000	)	$	(1,227,000	)
Amounts recognized in accumulated other comprehensive (loss) income:
Net actuarial loss (gain)	$	3,038,000		$	2,068,000		$	506,000		$	530,000		$	(110,000	)	$	(155,000	)
Prior service cost (credit)	77,000			81,000			(76,000		)	(80,000		)	—			—
Accumulated other comprehensive loss (income)	$	3,115,000		$	2,149,000		$	430,000		$	450,000		$	(110,000	)	$	(155,000	)

Schedule of weighted-average assumptions used to determine benefit obligations and net periodic benefit costs

The following table presents the weighted-average assumptions used to determine benefit obligations and net benefit costs:

	Pension		SERP		Postretirement Medical
	Year ended September 30,
	2015	2014	2015	2014	2015	2014
Assumptions used to determine fiscal year-end benefit obligations:
Discount rate	4.25%	4.25%	4.25%	4.25%	4.25%	4.25%
Rate of compensation increase	4.00%	4.00%	4.00%	4.00%	N/A	N/A
Assumptions used to determine net benefit costs (years ended):
Discount rate	4.25%	5.00%	4.25%	5.00%	4.25%	5.00%
Expected return on plan assets	7.00%	7.00%	N/A	N/A	N/A	N/A
Rate of compensation increase	4.00%	4.00%	4.00%	4.00%	N/A	N/A

Schedule of components of net periodic benefit cost

The components of net periodic benefit cost are as follows:

	Pension						SERP						Postretirement Medical
	Year ended September 30,
	2015			2014			2015			2014			2015			2014
Net periodic benefit cost for the year:
Service cost	$	256,000		$	156,000		$	62,000		$	47,000		$	—		$	12,000
Interest cost	356,000			322,000			77,000			67,000			52,000			54,000
Expected return on plan assets	(500,000		)	(429,000		)	—			—			—			—
Amortization of prior service cost (credit)	5,000			5,000			(5,000		)	(5,000		)	—			12,000
Amortization of net actuarial loss (gain)	86,000			20,000			24,000			5,000			(5,000		)	(21,000		)
Net periodic benefit cost	$	203,000		$	74,000		$	158,000		$	114,000		$	47,000		$	57,000

Schedule of amounts that are estimated to be amortized from accumulated other comprehensive loss into net periodic benefit cost in the next fiscal year

The amounts that are estimated to be amortized from accumulated other comprehensive loss into net periodic benefit cost in the next fiscal year are as follows:

	Pension		SERP			Postretirement Medical
Prior service cost (credit)	$	5,000	$	(5,000	)	$	—
Net actuarial loss (gain)	135,000		19,000			(5,000		)
	$	140,000	$	14,000		$	(5,000	)

Schedule of benefits expected to be paid under the retirement plans

The benefits expected to be paid under the retirement plans as of September 30, 2015 are as follows:

	Pension		SERP		Postretirement Medical
Expected Benefit Payments:
Fiscal year ending September 30, 2016	$	207,000	$	5,000	$	—
Fiscal year ending September 30, 2017	$	268,000	$	4,000	$	—
Fiscal year ending September 30, 2018	$	288,000	$	3,000	$	25,000
Fiscal year ending September 30, 2019	$	275,000	$	3,000	$	28,000
Fiscal year ending September 30, 2020	$	383,000	$	71,000	$	19,000
Fiscal years ending September 30, 2021 through 2025	$	2,380,000	$	568,000	$	296,000

Schedule of assumed health care cost trend rates related to the measurement of postretirement medical obligations

The following table provides the assumed health care cost trend rates related to the measurement of Barnwell’s postretirement medical obligations.

	Year ended September 30,
	2015	2014
Health care cost trend rates assumed for next year	8.0%	7.5%
Ultimate cost trend rate	5.0%	5.0%
Year that the rate reaches the ultimate trend rate	2028	2020

Schedule of effects of one-percentage-point change in the assumed health care cost trend rates

A one-percentage-point change in the assumed health care cost trend rates would have the following effects:

	1-Percentage Point Increase		1-Percentage Point (Decrease)
Effect on total service and interest cost components	$	11,000	$	(9,000	)
Effect on accumulated postretirement benefit obligations	$	267,000	$	(212,000	)

Schedule of year-end target allocation, by asset category, and the actual asset allocations

The Company’s year-end target allocation, by asset category, and the actual asset allocations were as follows:

	Target	September 30,
Asset Category	Allocation	2015	2014
Cash and other	0% - 30%	9%	12%
Fixed income securities	20% - 60%	22%	20%
Equity securities	30% - 70%	69%	68%

Schedule of pension plan assets at fair value

The following tables set forth by level, within the fair value hierarchy, pension plan assets at their fair value:

			Fair Value Measurements Using:
	Carrying Amount as of September 30, 2015		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Financial Assets:
Cash	$	621,000	$	621,000	$	—	$	—
Corporate bonds	354,000		354,000		—		—
Fixed income exchange-traded funds	819,000		819,000		—		—
Preferred securities	230,000		230,000		—		—
Equity securities exchange-traded funds	764,000		764,000		—		—
Equities	3,700,000		3,700,000		—		—
Total	$	6,488,000	$	6,488,000	$	—	$	—
			Fair Value Measurements Using:
	Carrying Amount as of September 30, 2014		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Financial Assets:
Cash	$	817,000	$	817,000	$	—	$	—
Corporate bonds	660,000		660,000		—		—
Fixed income exchange-traded funds	521,000		521,000		—		—
Preferred securities	232,000		232,000		—		—
Equity securities exchange-traded funds	758,000		758,000		—		—
Equities	4,034,000		4,034,000		—		—
Total	$	7,022,000	$	7,022,000	$	—	$	—