Details of Selected Consolidated Balance Sheet Captions

The following tables provide additional information regarding the composition of certain of our balance sheet captions.

Accounts receivable

Accounts receivable was comprised of the following at September 30, 2016 and 2015:



	September 30
	2016			2015
	(In thousands)
Billed accounts receivable	$	206,248		$	204,585
Unbilled revenue	67,396			65,008
Other accounts receivable	39,730			40,850
Total accounts receivable	313,374			310,443
Less: allowance for doubtful accounts	(13,367		)	(15,283		)
Net accounts receivable	$	300,007		$	295,160

Other current assets

Other current assets as of September 30, 2016 and 2015 were comprised of the following accounts.



	September 30
	2016		2015
	(In thousands)
Assets from risk management activities	$	9,804	$	9,232
Deferred gas costs	45,184		9,715
Taxes receivable	5,456		4,479
Prepaid expenses	23,053		23,055
Materials and supplies	5,825		12,587
Other	11,507		6,822
Total	$	100,829	$	65,890

Property, plant and equipment

Property, plant and equipment was comprised of the following as of September 30, 2016 and 2015:



	September 30
	2016			2015
	(In thousands)
Production plant	$	66		$	131
Storage plant	353,523			286,011
Transmission plant	2,232,927			1,844,117
Distribution plant	6,598,990			6,019,001
General plant	761,057			769,311
Intangible plant	40,515			41,131
	9,987,078			8,959,702
Construction in progress	184,062			280,398
	10,171,140			9,240,100
Less: accumulated depreciation and amortization	(1,890,629		)	(1,809,520		)
Net property, plant and equipment⁽¹⁾	$	8,280,511		$	7,430,580


⁽¹⁾	Net property, plant and equipment includes plant acquisition adjustments of $(59.8) million and $(68.1) million at September 30, 2016 and 2015.

Goodwill

The following presents our goodwill balance allocated by segment and changes in the balance for the fiscal year ended September 30, 2016:



	Regulated Distribution		Regulated Pipeline		Nonregulated		Total
	(In thousands)
Balance as of September 30, 2015	$	575,449	$	132,542	$	34,711	$	742,702
Deferred tax adjustments on prior acquisitions⁽¹⁾	665		40		—		705
Balance as of September 30, 2016	$	576,114	$	132,582	$	34,711	$	743,407


⁽¹⁾	We annually adjust certain deferred taxes recorded in connection with acquisitions completed in fiscal 2001 and fiscal 2004, which resulted in an increase to goodwill and net deferred tax liabilities of $0.7 million for fiscal 2016.

Deferred charges and other assets

Deferred charges and other assets as of September 30, 2016 and 2015 were comprised of the following accounts.



	September 30
	2016		2015
	(In thousands)
Marketable securities	$	72,701	$	74,200
Regulatory assets	214,890		182,573
Assets from risk management activities	1,822		368
Other	15,872		18,343
Total	$	305,285	$	275,484

Accounts payable and accrued liabilities

Accounts payable and accrued liabilities as of September 30, 2016 and 2015 were comprised of the following accounts.

Other current liabilities

Other current liabilities as of September 30, 2016 and 2015 were comprised of the following accounts.



	September 30
	2016		2015
	(In thousands)
Customer credit balances and deposits	$	81,890	$	100,232
Accrued employee costs	47,058		47,602
Deferred gas costs	20,180		28,100
Accrued interest	34,863		34,914
Liabilities from risk management activities	56,771		9,568
Taxes payable	104,457		93,674
Pension and postretirement obligations	36,606		21,857
Current deferred tax liability	—		55,918
Regulatory cost of removal accrual	52,610		56,123
Other	14,601		9,966
Total	$	449,036	$	457,954

Deferred credits and other liabilities

Deferred credits and other liabilities as of September 30, 2016 and 2015 were comprised of the following accounts.



	September 30
	2016		2015
	(In thousands)
Customer advances for construction	$	9,850	$	9,316
Regulatory liabilities	4,152		3,693
Asset retirement obligation	13,404		9,063
Liabilities from risk management activities	184,048		110,539
Other	34,236		29,085
Total	$	245,690	$	161,696