Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 9,467	$ 12,115	$ 5,146
Adjustments to reconcile net income to cash flows provided by operating activities:
Depreciation	6,906	7,001	7,137
Amortization	326	376	885
Amortization of loan costs	476	4,823	1,397
Loss on debt prepayment penalty		2,303
Provision (benefit) for deferred income taxes	1,062	(9,393)	2,142
Excess tax benefit from stock-based compensation	144	52	32
Provision for uncollectible accounts receivable	553	357	348
Stock-based compensation	308	308	415
Payment in kind interest - subordinated debt		266	273
Changes in operating assets and liabilities
Accounts receivable	(113)	(316)	(4)
Materials and supplies	(102)	(516)	(278)
Prepaid expenses and other assets	1,982	(189)	(100)
Accounts payable and accrued expenses	(37)	215	(178)
Advance billings and payments	(203)	577	1,428
Other liabilities	(9)	(17)	(6)
Net cash from operating activities	20,760	17,962	18,637
Cash flows used in investing activities:
Acquisition and construction of property and equipment	(7,983)	(8,510)	(6,879)
Retirement of investment	(11)	(1)	(1)
Net cash used in investing activities	(7,994)	(8,511)	(6,880)
Cash flows used in financing activities:
Loan origination costs	(64)	(2,144)	(5,242)
Principal repayment of long-term notes payable	(11,350)	(98,927)	(103,052)
Proceeds from loan refinancing		87,000	100,300
Debt prepayment penalty fees		(2,303)
Interest rate cap	(4)
CoBank equity account retirement	119	164
Tax withholdings paid on behalf of employees for restricted stock units	(380)	(209)	(109)
Net cash used in financing activities	(11,679)	(16,419)	(8,103)
Net increase (decrease) in cash and cash equivalents	1,087	(6,968)	3,654
Cash and cash equivalents, beginning of period	3,570	10,538	6,884
Cash and cash equivalents, end of period	4,657	3,570	10,538
Supplemental disclosures of cash flow information:
Interest paid	5,383	9,287	8,364
Income taxes (refunded) paid	(502)	1,802	1,923
Conversion of Class B common stock to Class A common stock			2
Issuance of Class A common stock		$ 1	$ 1