Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2018

Accounting Policies [Abstract]

Disaggregation of Revenue

In the following tables, revenue from contracts with customers is disaggregated by class of customers for the three and six month periods ended June 30, 2018 and 2017:

	Three Months Ended June 30
	2018		2017
Residential	$	109,849	$	102,171
Business	32,125		29,543
Industrial	7,941		6,408
Public authorities	8,251		7,874
Other	13,606		16,597
Total revenue from contracts with customers	$	171,772	$	162,593

	Six Months Ended June 30
	2018		2017
Residential	$	201,167	$	178,036
Business	59,182		51,569
Industrial	15,520		13,363
Public authorities	13,695		12,020
Other	16,462		20,417
Total revenue from contracts with customers	$	306,026	$	275,405

The following tables disaggregate the Company’s non-regulated revenue by source for the three and six month periods ended June 30, 2018 and 2017:

	Three Months Ended June 30
	2018		2017
Operating and maintenance revenue	$	2,297	$	2,053
Other non-regulated revenue	1,981		1,178
Non-regulated revenue from contracts with customers	$	4,278	$	3,231
Lease revenue	$	567	$	508
Total non-regulated revenue	$	4,845	$	3,739

	Six Months Ended June 30
	2018		2017
Operating and maintenance revenue	$	5,462	$	3,966
Other non-regulated revenue	2,724		2,220
Non-regulated revenue from contracts with customers	$	8,186	$	6,186
Lease revenue	$	1,078	$	1,015
Total non-regulated revenue	$	9,264	$	7,201

The following tables disaggregate the Company’s operating revenue by source for the three and six month periods ended June 30, 2018 and 2017:

	Three Months Ended June 30
	2018		2017
Revenue from contracts with customers	$	171,772	$	162,593
Regulatory balancing account revenue	860		8,539
Total operating revenue	$	172,632	$	171,132

	Six Months Ended June 30
	2018			2017
Revenue from contracts with customers	$	306,026		$	275,405
Regulatory balancing account revenue	(1,147		)	17,763
Total operating revenue	$	304,879		$	293,168

Schedule of Cash, Cash Equivalents, and Restricted Cash

The following table provides a reconciliation of cash, cash equivalents, and restricted cash within the Condensed Consolidated Balance Sheets that sum to the total of the same such amounts shown on the Condensed Consolidated Statements of Cash Flows:

	June 30, 2018		December 31, 2017
Cash and cash equivalents	33,668		94,776
Restricted cash (included in "taxes, prepaid expenses and other assets")	597		576
Total cash, cash equivalents, and restricted cash shown in the statements of cash flows	$	34,265	$	95,352

Schedule of New Accounting Pronouncements and Changes in Accounting Principles

The following tables show the effect of the accounting change to the Condensed Consolidated Statements of Income for the three and six month periods ended June 30, 2017:

	Three Months Ended June 30, 2017
Condensed Consolidated Statement of Income line item	As Reported on Form 10-Q			Adjusted Balance on Form 10-Q			Increase (Decrease) from Retrospective Adoption
Administrative and general	$	23,796		$	21,413		$	(2,383	)
Income taxes	$	9,635		$	10,606		$	971
Total operating expenses	$	145,873		$	144,461		$	(1,412	)
Net operating income	$	25,259		$	26,671		$	1,412
Other components of net periodic benefit cost	$	—		$	(2,383	)	$	2,383
Income tax expense on other income and expense	$	(1,217	)	$	(246	)	$	971
Net other income	$	1,787		$	375		$	(1,412	)

	Six Months Ended June 30, 2017
Condensed Consolidated Statement of Income line item	As Reported on Form 10-Q			Adjusted Balance on Form 10-Q			Increase (Decrease) from Retrospective Adoption
Administrative and general	$	49,045		$	44,159		$	(4,886	)
Income taxes	$	8,751		$	9,722		$	971
Total operating expenses	$	259,859		$	255,944		$	(3,915	)
Net operating income	$	33,309		$	37,224		$	3,915
Other components of net periodic benefit cost	$	—		$	(4,886	)	$	4,886
Income tax expense on other income and expense	$	(2,106	)	$	(1,135	)	$	971
Net other income	$	3,085		$	(830	)	$	(3,915	)

The following table shows the effect of the accounting change to the Condensed Consolidated Statements of Cash Flows:

	Six Months Ended June 30, 2017
Condensed Consolidated Statements of Cash Flows line item	As Reported on Form 10-Q			Adjusted Balance on Form 10-Q			Increase (Decrease) from Retrospective Adoption
Change in restricted cash	$	(598	)	$	—		$	598
Net cash used in investing activities	$	(110,076	)	$	(109,478	)	$	598
Change in cash, cash equivalents, and restricted cash	$	3,611		$	4,209		$	598
Cash, cash equivalents, and restricted cash at beginning of period	$	25,492		$	25,935		$	443
Cash, cash equivalents, and restricted cash at end of period	$	29,103		$	30,144		$	1,041