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Acquisition Purchase Price Allocation (Details) (USD $)	0 Months Ended
Acquisition Purchase Price Allocation (Details) (USD $)	Oct. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Aug. 31, 2013
Business Acquisition [Line Items]
Contingent consideration		$ 26,542,000		$ 500,000
Goodwill		15,545,000us-gaap_Goodwill	0us-gaap_Goodwill
RedPath Integrated Pathology, Inc
Business Acquisition [Line Items]
Cash	13,572,000
Cash	22,066,000
Common stock	1,820,000
Contingent consideration	23,886,000
Total consideration	44,854,000
Goodwill	15,545,000
Acquired intangible assets	34,492,000
Current assets	5,465,000
Other long-term assets	366,000
Current liabilities	(4,809,000)
Deferred income tax liability	(6,205,000)
Total acquired assets	44,854,000
Diagnostic Test - Pancreas \| RedPath Integrated Pathology, Inc
Business Acquisition [Line Items]
Acquired intangible assets	16,141,000
Diagnostic Test - Barrett's RedPath \| RedPath Integrated Pathology, Inc
Business Acquisition [Line Items]
Acquired intangible assets	18,351,000
Notes Payable, Other Payables
Business Acquisition [Line Items]
Subordinated note payable	11,000,000
Notes Payable, Other Payables \| RedPath Integrated Pathology, Inc
Business Acquisition [Line Items]
Subordinated note payable	$ 7,396,000