Discontinued Operations - Supplemental Cash Flow Information (Details) - MDSS post-warranty service business - Discontinued operations, disposed of by sale - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating activities
Depreciation, Discontinued Operations			$ 0	$ 0
Amortization of intangible assets	$ 0	$ 0	0	0
Gain on sale of discontinued operations	$ 0	$ (350)	0	(350)
Share-based Compensation, Discontinued Operations			0	0
Investing activities
Proceeds from sale of discontinued operations			$ 0	$ 0

Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 205
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-URI http://asc.fasb.org/extlink&oid=109222160&loc=SL51721525-107759

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