COMMITMENTS AND CONTINGENCIES (Details)	Dec. 31, 2018 USD ($)
Long-term Purchase Commitment [Line Items]
2019	$ 5,899,000
Thereafter	39,859,000
Total	45,758,000
Proton Beam Unit [Member]
Long-term Purchase Commitment [Line Items]
2019	0
Thereafter	34,000,000
Total	34,000,000
Gamma Knife and Linac Units [Member]
Long-term Purchase Commitment [Line Items]
2019	4,235,000
Thereafter	0
Total	4,235,000
Service Contacts [Member]
Long-term Purchase Commitment [Line Items]
2019	1,664,000
Thereafter	5,859,000
Total	$ 7,523,000

Minimum amount of other commitment maturing in the next fiscal year following the latest fiscal year for commitments not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in this taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

No definition available.

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