2. Acquisitions (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Apr. 01, 2020	Oct. 01, 2019
Business Combinations [Abstract]
Business Combination, Consideration Transferred		$ 99,300	$ 4,200
Payments to Acquire Businesses, Net of Cash Acquired			3,600
Business Combination, Contingent Consideration, Liability							$ (100)	$ (600)
Business Combination, Separately Recognized Transactions, Revenues and Gains Recognized			$ 400
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles								3,400
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets							8,400	200
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net							300	1,400
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High							60,000
Payments to Acquire Businesses, Gross		99,200
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents							600
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities							(19,700)	$ (800)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill							79,900
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net							99,300
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets							$ 69,500
Proceeds from Divestiture of Businesses		12,200			$ 12,240	$ 0
Gain (Loss) on Disposition of Business	$ 0	11,700		$ 0	11,700	0
Business Combination, Goodwill [Abstract]
Goodwill, Acquired During Period		29,800			29,800
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization expense	7,200			$ 6,000	20,300	$ 17,100
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities
Goodwill [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Assets	400
Other Noncurrent Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Assets	(300)
Other Noncurrent Liabilities [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities	300
Celsee, Inc. [Member] | Cost of Sales [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization expense	900				1,800
In Process Research and Development [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets Acquired		4,600
Developed Technology Rights [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired		$ 70,300
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		18 years 10 months 24 days
Customer Lists [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired		$ 3,600
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		4 years
Customer Lists [Member] | Celsee, Inc. [Member] | Selling, General and Administrative Expenses [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization expense	200				400
Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired		$ 1,400
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		3 years
Noncompete Agreements [Member] | Celsee, Inc. [Member] | Selling, General and Administrative Expenses [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 100				$ 200