Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash Flows from Operating Activities:
Net income (loss)	$ 5,471	$ (3,538)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	16,984	17,931
Loss on disposal of assets, net	41	33
Amortization of debt issuance costs and debt discount	689	1,537
Loss on extinguishment of debt		7,434
Amortization of deferred capacity revenue	(1,930)	(1,717)
Stock-based compensation	567	581
Income tax expense (benefit)	1,306	(1,464)
Charge for uncollectible accounts	1,092	1,633
Other non-cash expense, net	181	288
Income taxes (receivable) payable	(36)	574
Changes in operating assets and liabilities	(2,007)	(6,227)
Net cash provided by operating activities	22,358	17,065
Cash Flows from Investing Activities:
Capital expenditures	(17,081)	(10,522)
Capitalized interest	(891)	(463)
Change in unsettled capital expenditures	(1,632)	(2,043)
Proceeds on sale of assets		4
Net cash used by investing activities	(19,604)	(13,024)
Cash Flows from Financing Activities:
Repayments of long-term debt	(20,506)	(174,013)
Proceeds from the issuance of long-term debt	14,000	183,000
Debt issuance costs and discounts		(5,508)
Cash paid for debt extinguishment		(5,279)
Cash proceeds from noncontrolling interest	40
Payment of withholding taxes on stock-based compensation	(410)	(599)
Proceeds from the issuance of common stock	111	119
Net cash used by financing activities	(6,765)	(2,280)
Change in cash, cash equivalents and restricted cash	(4,011)	1,761
Cash, cash equivalents and restricted cash, beginning of period	16,168	23,145
Cash, cash equivalents and restricted cash, end of period	12,157	24,906
Supplemental Cash Flow Data:
Interest paid	7,251	7,595
Income taxes paid (refunded), net	$ 4	$ (572)