Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

SUBSEQUENT EVENTS - LSV Co-Invest I and LSVM Waivers (Details) - Promissory Note - USD ($)	Jun. 30, 2019	Dec. 17, 2018	Dec. 14, 2018	Jun. 30, 2018	Jun. 01, 2018	Jan. 31, 2018	Jan. 12, 2018
Unsecured Promissory Note
Subsequent Event [Line Items]
Debt principal amount				$ 900,000.0	$ 900,000.0	$ 500,000.0	$ 500,000.0
Digirad Unsecured Promissory Note, Issued December 12, 2018
Subsequent Event [Line Items]
Debt principal amount	$ 300,000	$ 300,000	$ 300,000.0