Slicers (applies to each fact value in each table cell)

Reporting Entity [Axis]

0000744825 (http://www.sec.gov/CIK)

Property, Plant and Equipment [Abstract]	Period [Axis]
	2016-01-01 - 2016-12-31
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment [Table Text Block]	Property and equipment consists of the following:       DECEMBER 31,       2016   2015               Medical equipment and facilities   $ 96,270,000   $ 83,267,000   Office equipment     537,000     721,000   Deposits and construction in progress     6,073,000     5,796,000   Deposits towards purchase of proton beam systems     2,000,000     5,000,000                         104,880,000     94,784,000   Accumulated depreciation     (53,549,000)     (47,661,000)                   Net property and equipment   $ 51,331,000   $ 47,123,000