Consolidated Statements of Cash Flows $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
OPERATING ACTIVITIES
Net loss	$ (8,165)	$ (13,808)	$ (6,079)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, amortization and other	30,762	22,796	23,386
Stock-based compensation expense	9,061	7,986	7,419
Amortization of debt discount and deferred issuance costs	6,022	5,891	5,664
Change in fair value of acquisition contingencies	(81)	(485)	(88)
Accretion of interest on deferred consideration		0	0
Amortization of inventory step-up to fair value	10,950	0	0
Change in fair value of acquisition contingencies	365	(2,603)	(4,027)
Gain on extinguishment of Convertible Senior Notes	0	(421)	0
Excess tax benefit from share-based compensation
Accounts receivable	(42,052)	(6,265)	16,060
Inventories	362	859	(1,637)
Prepaid expenses and other current and non-current assets	(9,113)	(552)	(1,039)
Restricted cash	0	63	3,064
Accounts payable	12,956	4,323	(3,082)
Accrued payroll and related expenses	7,130	(375)	1,061
Deferred grant revenue	0	(3,658)	(2,672)
Other current and non-current liabilities	6,904	(1,936)	(1,150)
Net cash provided by operating activities	27,709	11,815	36,880
INVESTING ACTIVITIES
Acquisitions of property, equipment and intangibles	(17,510)	(11,909)	(17,032)
Acquisition of other businesses, net of cash acquired	(14,451)	(5,061)	0
Acquisition of Triage and BNP Businesses	(399,798)	0	0
Net cash used for investing activities	(431,759)	(16,970)	(17,032)
FINANCING ACTIVITIES
Proceeds from issuance of Term Loan	245,000	0	0
Proceeds from issuance of Revolving Credit Facility	10,000	0	0
Proceeds from issuance of common stock	25,426	8,575	2,911
Payments of debt issuance costs	(8,682)	0	(365)
Payments on lease obligation	(98)	(540)	(509)
Repurchases of common stock	(541)	(20,168)	(30,934)
Repurchases of Convertible Senior Notes	0	(4,459)	0
Payments on acquisition contingencies	(497)	(207)	(129)
Payment for acquisition holdback	0	0	(229)
Net cash provided by (used for) financing activities	270,608	(16,799)	(29,255)
Effect of exchange rate changes on cash	20	(9)	(17)
Net decrease in cash and cash equivalents	(133,422)	(21,963)	(9,424)
Cash and cash equivalents, beginning of period	169,508	191,471	200,895
Cash and cash equivalents, at end of period	36,086	169,508	191,471
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Cash paid during the period for interest	9,137	6,488	6,998
Cash paid during the period for income taxes	1,274	490	1,922
NON-CASH INVESTING ACTIVITIES
Purchase of property, equipment and intangibles by incurring current liabilities	1,446	3,280	239
NON-CASH FINANCING ACTIVITIES
Decrease of accrued payroll and related expenses upon issuance of common stock	903	539	408
Receivable for stock option exercises	$ 0	251	0
Deferred consideration for acquisition of BNP Business		$ 0	$ 0