Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash Flows From Operating Activities
Net Income	$ 5,262,335	$ 6,500,545
Adjustments to reconcile net income (loss) to net cash from operating activities
Depreciation and amortization	5,004,487	4,913,293
Deferred income taxes and investment tax credits	1,168,847	815,773
Change in cash surrender value of officer's life insurance	15,605	(11,471)
Share-based compensation	383,482	1,034,672
Excess tax deficiency from share-based compensation	(7,581)	(9,574)
Decrease in assets	1,477,572	578,429
Decrease (increase) in liabilities	(1,424,599)	341,589
Net cash provided by operating activities	11,880,148	14,163,256
Cash Flows From Investing Activities
Capital expenditures	(4,943,907)	(6,402,067)
Proceeds from sale of property, plant and equipment	249,163	34,822
Other	(60,000)	(60,000)
Net cash used in investing activities	(4,754,744)	(6,427,245)
Cash Flows From Financing Activities
Dividends on common shares	(4,364,616)	(4,227,814)
Issuance of common shares	483,996	398,764
Excess tax benefit from share-based compensation	2,073	18,823
Payments Related to Tax Withholding for Share-based Compensation	(263,044)	0
Repayments of long-term debt	(1,500,000)	(1,500,000)
Borrowing on bank line of credit	0	126,430
Repayments on Lines of Credit	0	(126,430)
Net cash used in financing activities	(5,641,591)	(5,310,227)
Net Increase in Cash and Cash Equivalents	1,483,813	2,425,784
Cash and Cash Equivalents, Beginning of Period	16,924,278	13,675,918
Cash and Cash Equivalents, End of Period	$ 18,408,091	$ 16,101,702