Vectren Fuels Acquisition (Schedule of Business Acquisition Pro Forma Information) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Revenues [Abstract]
As reported	$ 233,902	$ 137,436
Net income applicable to common shareholders
As reported	9,844
Net Income per Share [Abstract]
As reported	$ 0.34	$ 0.78
Vectren Fuels [Member]
Revenues [Abstract]
As reported	241,171	153,870
Pro forma	462,000	447,500
Net income applicable to common shareholders
As reported	10,219	22,423
Pro forma	$ 39,068	$ 46,503
Net Income per Share [Abstract]
As reported	$ 0.34	$ 0.78
Pro forma	$ 1.36	$ 1.63