REGULATORY MATTERS (Details 2) (USD $)	12 Months Ended		0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 05, 2014	Jun. 17, 2011	Apr. 01, 2012	Jun. 13, 2012	Jul. 06, 2012	Apr. 02, 2013	Aug. 29, 2014	Nov. 23, 2012	Oct. 18, 2012	May 21, 2012	Jan. 02, 2012	Jan. 04, 2012	Jun. 30, 2011	Sep. 26, 2014	Dec. 03, 2013
RATE MATTERS
Plant Disallowance	$ 86,000	$ 2,409,000
Utilities Operating Expense Reverse Gain on Sale of Assets	44,000	1,236,000
Missouri Public Service Commission (MPSC) | Missouri 2012 Rate Case
RATE MATTERS
Write-off of various items including disallowance for the prudency of certain construction expenditures	3,600,000
Utilities Operating Expense Reverse Gain on Sale of Assets	1,200,000
Requested amount of annual increase in electric base rate							30,700,000
Percentage of annual base rate increase requested							7.56%
Missouri Public Service Commission (MPSC) | Missouri 2012 Rate Case | Iatan2
RATE MATTERS
Plant Disallowance	2,400,000
Missouri Public Service Commission (MPSC) | Electric
RATE MATTERS
Approved amount of annual increase in base rate								27,500,000
Approved percentage of annual increase in base rate								6.78%
Missouri Public Service Commission (MPSC) | Electric | Missouri 2014 Rate Case
RATE MATTERS
Requested amount of annual increase in base rate									24,300,000
Requested percentage of annual increase in base rate									5.50%
Missouri Public Service Commission (MPSC) | Electric | Tornado Recovery
RATE MATTERS
Deferred depreciation, operations and maintenance, and carrying costs related to capital expenditure	4,000,000
Amortization period for deferred asset related to the tax benefits of cost of removal	10 years
Missouri Public Service Commission (MPSC) | Water
RATE MATTERS
Approved amount of annual increase in base rate										450,000
Approved percentage of annual increase in base rate										25.50%
Missouri Public Service Commission (MPSC) | Water | Missouri 2012 Rate Case
RATE MATTERS
Requested amount of annual increase in electric base rate												516,400
Percentage of annual base rate increase requested												29.60%
Amount of increase in base rate for which unanimous agreement filed											450,000
Kansas Corporation Commission (KCC) | 2014 Environmental Cost Recovery Rider Member
RATE MATTERS
Proposed recover costs			859,674
Kansas Corporation Commission (KCC) | Electric
RATE MATTERS
Approved amount of annual increase in base rate													1,250,000
Approved percentage of annual increase in base rate													5.20%
Kansas Corporation Commission (KCC) | Electric | Kansas 2011 Rate Case
RATE MATTERS
Requested amount of annual increase in electric base rate				1,500,000
Percentage of annual base rate increase requested				6.39%
Period to recover costs				3 years
Oklahoma Corporation Commission (OCC) | Electric
RATE MATTERS
Approved amount of annual increase in base rate														240,722
Approved percentage of annual increase in base rate														1.66%
Requested amount of annual increase in electric base rate															600,000
Percentage of annual base rate increase requested															4.10%
Base rate revenue included in authorized amount of increase in annual revenues					200,000
Arkansas Public Service Commission (APSC) | Electric
RATE MATTERS
Approved amount of annual increase in base rate																1,366,809
Approved percentage of annual increase in base rate																11.34%
Arkansas Public Service Commission (APSC) | Electric | Arkansas 2013 Rate Case
RATE MATTERS
Requested amount of annual increase in electric base rate	$ 1,375,000																$ 2,200,000
Percentage of annual base rate increase requested	11.00%																18.00%
Federal Energy Regulatory Commission (FERC) | TFR rate case
RATE MATTERS
Percentage of ROE						10.00%