Acquisitions (Narrative) (Details) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2017 USD ($) entity	Jun. 30, 2017 USD ($) entity	Mar. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)
Business Acquisition [Line Items]
Acquisition of a business, net of cash acquired				$ 14,529
Reference Laboratory In United States [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred	$ 1,300
Number of businesses acquired | entity	3
Two Software Companies [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 15,000
Acquisition of a business, net of cash acquired		$ 12,000
Number of businesses acquired | entity		2
Business Combination, Contingent Consideration, Term For Payment Upon Completion Of Goals		36 months
Contingent payment		$ 3,000
Business Combinations, goodwill		13,300
Reference Laboratory In Austria [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred			$ 1,300
Customer Relationships [Member] | Two Software Companies [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		1,000
Technology-Based Intangible Assets [Member] | Two Software Companies [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		$ 600