Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Gamma Knife, accumulated depreciation	$ 0	$ 1,372,000
Leasehold improvement, accumulated amortization	$ 0	$ 134,000
STOCKHOLDERS' EQUITY
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	25,000,000	25,000,000
Common stock, shares issued (in shares)	7,797,185	7,797,185
Common stock, shares outstanding (in shares)	7,797,185	7,797,185