Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Cash Flows from Operating Activities:
Net income (loss)	$ 8,988	$ (6,230)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	33,908	36,317
Loss on the disposal of assets	125	50
Amortization of debt issuance costs and debt discount	1,353	2,363
Loss on extinguishment of debt		7,527
Amortization of deferred capacity revenue	(4,098)	(3,512)
Stock-based compensation	1,757	1,509
Income tax expense	2,041	2,584
Charge for uncollectible accounts	2,745	3,577
Other non-cash expense, net	225	575
Change in income tax payable or receivable	(729)	(8,052)
Changes in operating assets and liabilities	9,880	(6,302)
Net cash provided by operating activities	56,195	30,406
Cash Flows from Investing Activities:
Capital expenditures	(37,957)	(32,945)
Capitalized interest	(2,001)	(1,140)
Change in unsettled capital expenditures	(227)	1,500
Proceeds on sale of assets	1	40
Net cash used by investing activities	(40,184)	(32,545)
Cash Flows from Financing Activities:
Repayments of long-term debt	(31,030)	(176,466)
Proceeds from the issuance of long-term debt	14,000	183,000
Debt issuance costs		(5,559)
Cash paid for debt extinguishment		(5,522)
Cash proceeds from noncontrolling interest	40	75
Payment of withholding taxes on stock-based compensation	(415)	(605)
Proceeds from the issuance of common stock	211	239
Net cash used by financing activities	(17,194)	(4,838)
Change in cash and cash equivalents and restricted cash	(1,183)	(6,977)
Cash and cash equivalents and restricted cash, beginning of period	16,168	23,145
Cash and cash equivalents and restricted cash, end of period	14,985	16,168
Supplemental Cash Flow Data:
Interest paid	14,254	14,504
Income taxes paid (refunded), net	$ 3	$ (946)