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ACCOUNTING POLICIES (Details Textual) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Jan. 01, 2019
Accounting Policies [Line Items] |  |  |  |
Interest Costs Capitalized | $ 115,000 | $ 138,000 | $ 443,000 |
Property Subject to or Available for Operating Lease, Net, Total | 94,031,000 | 95,923,000 |  |
Property Subject to or Available for Operating Lease, Accumulated Depreciation | $ 53,716,000 | $ 51,403,000 |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 519,000 | 14,000 | 581,000 |
Stock Options Exercise Price |  | $ 3.90 |  |
Advertising Expense | $ 113,000 | $ 140,000 | $ 279,000 |
Insurance Settlements Receivable, Current | 1,137,000 | $ 0 |  |
Revenue from Contract with Customer, Including Assessed Tax | $ 18,987,000 |  |  |
Percentage of Tax Benefit Realized Upon Settlement | 50.00% |  |  |
Mevion Medical Systems Inc [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Gain on Business Interruption Insurance Recovery | $ 185,000 |  |  |
Sales Revenue, Net [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration Risk, Percentage | 100.00% | 100.00% | 100.00% |
Customer One [Member] | Sales Revenue, Net [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration Risk, Percentage | 26.00% | 21.00% | 10.00% |
Restricted Stock Units (RSUs) [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 4,000 | 4,000 | 4,000 |
Accounting Standards Update 2014-09 [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Revenue from Contract with Customer, Excluding Assessed Tax | $ 727,000 |  |  |
Accounting Standards Update 2016-02 [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Operating Lease, Right-of-Use Asset |  |  |  | $ 1,000,000
PBRT [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Property, Plant and Equipment, Useful Life | 20 years |  |  |
Mevion Medical Systems Inc [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Cost of Property Repairs and Maintenance | $ 977,000 |  |  |
Mevion Medical Systems Inc [Member] | Insurance Settlement Receivable Current [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Cost of Property Repairs and Maintenance | $ 977,000 |  |  |
Maximum [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Stock Options Exercise Price | $ 3.90 |  | $ 3.15 |
Maximum [Member] | Medical and Office equipment [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Property, Plant and Equipment, Useful Life | 10 years |  |  |
Minimum [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Stock Options Exercise Price | $ 2.82 |  | $ 2.43 |
Minimum [Member] | Customer Three [Member] | Accounts Receivable [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration Risk, Percentage | 10.00% | 10.00% |  |
Minimum [Member] | Medical and Office equipment [Member] |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |  |

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