Segment Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) segment	Mar. 31, 2019 USD ($)
Segment Reporting [Abstract]
Number of operating segments \| segment	2
Geographical revenues
Revenues	$ 90,704	$ 86,510
Operating income	7,125	16,169
Interest expense	1,946	4,592
Other income	(350)	(1,187)
Income before income taxes	5,529	12,764
DEFINITY
Geographical revenues
Revenues	56,791	51,111
TechneLite
Geographical revenues
Revenues	23,098	24,145
Other nuclear
Geographical revenues
Revenues	15,500	15,120
Rebates and allowances
Geographical revenues
Revenues	4,685	3,866
U.S.
Geographical revenues
Revenues	78,745	75,434
Operating income	4,988	14,584
U.S. \| DEFINITY
Geographical revenues
Revenues	55,010	49,716
U.S. \| TechneLite
Geographical revenues
Revenues	19,356	20,058
U.S. \| Other nuclear
Geographical revenues
Revenues	9,062	9,524
U.S. \| Rebates and allowances
Geographical revenues
Revenues	4,683	3,864
International
Geographical revenues
Revenues	11,959	11,076
Operating income	2,137	1,585
International \| DEFINITY
Geographical revenues
Revenues	1,781	1,395
International \| TechneLite
Geographical revenues
Revenues	3,742	4,087
International \| Other nuclear
Geographical revenues
Revenues	6,438	5,596
International \| Rebates and allowances
Geographical revenues
Revenues	$ 2	$ 2

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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