Amount classified as goodwill attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwillNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Goodwill (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jul. 22, 2020	Dec. 31, 2019
Acquired Indefinite-lived Intangible Assets [Line Items]
Goodwill	$ 98,333		$ 97,307
Discontinued operations, goodwill	$ 18,623		$ 18,623
OpenNMS Assignment \| Equity Method Investee
Acquired Indefinite-lived Intangible Assets [Line Items]
Goodwill		$ 1,026