Recently Adopted and Issued Accounting Guidance - Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Clinical Testing	$ 56,971	$ 52,907
Pharma Services	6,452	4,521
Total Revenue	63,423	57,428
Gross Profit	27,303	22,948
Total operating expenses	24,798	23,528
INCOME (LOSS) FROM OPERATIONS	2,505	(580)
Interest expense	1,486	1,364
Income tax (benefit) expense	438	(779)
Net income (loss)	$ 644	(1,165)
Scenario, Previously Reported
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Clinical Testing		56,690
Pharma Services		4,986
Total Revenue		61,676
Gross Profit		27,196
Total operating expenses		27,311
INCOME (LOSS) FROM OPERATIONS		(115)
Interest expense		1,364
Income tax (benefit) expense		(825)
Net income (loss)		(654)
Restatement Adjustment | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Clinical Testing		(3,783)
Pharma Services		(465)
Total Revenue		(4,248)
Gross Profit		(4,248)
Total operating expenses		(3,783)
INCOME (LOSS) FROM OPERATIONS		(465)
Interest expense		0
Income tax (benefit) expense		46
Net income (loss)		$ (511)