Note 9. Regulatory Assets and Liabilities

Regulatory assets and liabilities were comprised of the following as of March 31, 2015 and December 31, 2014:

	March 31, 2015		December 31, 2014
Regulatory Assets
Pension and retiree group health	$	244,843	$	245,008
Property-related temporary differences (tax benefits flowed through to ratepayers)	72,350		72,350
Other accrued benefits	32,684		32,959
Net WRAM and MCBA long-term accounts receivable	19,413		14,449
Asset retirement obligations, net	14,169		13,863
Interim rates long-term accounts receivable	8,996		10,627
Tank coating	5,097		—
Health care balancing account	1,875		1,075
Other regulatory assets	1,662		—
Total Regulatory Assets	$	401,089	$	390,331

Regulatory Liabilities
Future tax benefits due ratepayers	$	26,114	$	26,114
Conservation program	3,406		2,669
Pension balancing account	3,170		4,291
Other regulatory liabilities	2,412		3,373
Total Regulatory Liabilities	$	35,102	$	36,447

Short-term regulatory assets and liabilities are excluded from the above table. The short-term regulatory assets were $50.0 million as of March 31, 2015 and $53.2 million as of December 31, 2014. The short-term regulatory assets were primarily interim rates and net WRAM and MCBA accounts receivable as of March 31, 2015 and December 31, 2014. The short-term portions of regulatory liabilities were $5.6 million as of March 31, 2015 and $6.1 million as of December 31, 2014. The short-term regulatory liabilities were primarily net WRAM and MCBA liability balances and net refund balances to rate payers for the water conservation program from the 2009 General Rate Case (GRC).