CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net (loss) income	$ (1,479)	$ (15,306)	$ 13,979
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation, amortization and accretion	10,769	11,624	12,963
Deferred income tax (benefit) expense	(1,692)	25,390	6,926
Stock based compensation	4,954	3,688	854
Provisions for doubtful accounts, service credits and other		1,029	763
Adjustments of non-cash transaction taxes	(203)	(807)	(270)
Changes in assets and liabilities:
Accounts receivable	(915)	(9,648)	(1,790)
Prepaid expenses, intangible assets and other assets	(646)	244	824
Accounts payable, accrued liabilities and other	(1,553)	(3,278)	1,192
Deferred revenue	(1,045)	2,579	2,110
Net cash provided by operating activities	10,315	15,515	37,551
Cash flows from investing activities:
Purchases of property and equipment	(5,915)	(9,214)	(6,254)
Purchase of short-term investments	(3,911)	(3,957)	(3,975)
Maturity of short-term investments	4,000	4,000	2,000
Net cash used in investing activities	(5,826)	(9,171)	(8,229)
Cash flows from financing activities:
Cash distributions to stockholders	(10,064)	(15,234)	(10,287)
Purchase of common stock (including commissions)	(13,483)	(10,023)	(6,489)
Proceeds from issuance of common stock under the Employee Stock Purchase Plan	247	256	53
Purchase of common stock for tax withholding on vested equity awards	(976)	0	0
Net cash used in financing activities	(24,276)	(25,001)	(16,723)
Effect of exchange rate on cash	(49)	11	(109)
Net (decrease) increase in cash and cash equivalents	(19,836)	(18,646)	12,490
Cash and cash equivalents, beginning of period	103,179	121,825	109,335
Cash and cash equivalents, end of period	83,343	103,179	121,825
Supplemental disclosure:
Income taxes paid	$ 1,061	$ 2,620	$ 695