Operations by Business Segment (Tables)

6 Months Ended

Jun. 30, 2018

Segment Reporting [Abstract]

Schedule of segment reporting information, by segment [Table Text Block]

Segment information reconciled to consolidated external reporting information follows:

	Utility		Residential and Commercial		All Other			Reconciling Adjustments				Consolidated
Three Months Ended June 30, 2018
Revenues	$	128,496	$	141,465	$	688		$	—			$	270,649
Income (loss) from operations	6,265		26,834		(2,764		)	(535		)	(a)	29,800
Interest expense								(1,754		)		(1,754		)
Interest income								101				101
Other income (expense), net								(1,052		)		(1,052		)
Income before income taxes												$	27,095
Segment assets, total	$	197,287	$	222,638	$	—		$	73,329		(b)	$	493,254
Three Months Ended July 1, 2017
Revenues	$	112,903	$	131,299	$	835		$	—			$	245,037
Income (loss) from operations	4,270		23,837		(965		)	(1,483		)	(a)	25,659
Interest expense								(1,072		)		(1,072		)
Interest income								73				73
Other income (expense), net								(1,339		)		(1,339		)
Income before income taxes												$	23,321
Segment assets, total	$	171,472	$	202,502	$	—		$	86,198		(b)	$	460,172
Six Months Ended June 30, 2018
Revenues	$	247,183	$	230,810	$	1,307		$	—			$	479,300
Income (loss) from operations	8,079		23,729		(6,556		)	(1,118		)	(a)	24,134
Interest expense								(3,155		)		(3,155		)
Interest income								179				179
Other income (expense), net								(2,714		)		(2,714		)
Income before income taxes												$	18,444
Segment assets, total	$	197,287	$	222,638	$	—		$	73,329		(b)	$	493,254
Six Months Ended July 1, 2017
Revenues	$	225,381	$	210,886	$	1,583		$	—			$	437,850
Income (loss) from operations	6,928		20,255		(3,193		)	(2,326		)	(a)	21,664
Interest expense								(2,329		)		(2,329		)
Interest income								143				143
Other income (expense), net								(2,478		)		(2,478		)
Income before income taxes												$	17,000
Segment assets, total	$	171,472	$	202,502	$	—		$	86,198		(b)	$	460,172

Reconciling adjustments from segment reporting to consolidated external financial reporting include unallocated corporate items:

(a) Reclassification of depreciation expense and allocation of corporate expenses.

(b) Corporate assets include cash, prepaid expenses, corporate facilities, enterprise-wide information systems and other nonoperating assets.