Stock Incentive Plan and Employee Stock Purchase Plan (Details) (USD $)		12 Months Ended		12 Months Ended						1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended			1 Months Ended		12 Months Ended	1 Months Ended
	Jun. 30, 2013 item	Jun. 30, 2013 Stock options	Jun. 30, 2011 2007 Plan TomoTherapy	Jun. 30, 2013 2007 Plan Incentive stock option Minimum	Jun. 30, 2013 2007 Plan Non-qualified stock option Minimum	Jun. 30, 2013 2007 Plan Stock options	Jun. 30, 2012 2007 Plan Stock options	Jun. 30, 2011 2007 Plan Stock options	Jun. 30, 2010 2007 Plan Stock options	Jun. 30, 2011 2007 Plan Stock options TomoTherapy	Jun. 30, 2013 2007 Plan Stock options Minimum	Jun. 30, 2012 2007 Plan Stock options Minimum	Jun. 30, 2011 2007 Plan Stock options Minimum	Jun. 30, 2011 2007 Plan Stock options Minimum TomoTherapy	Jun. 30, 2013 2007 Plan Stock options Maximum	Jun. 30, 2012 2007 Plan Stock options Maximum	Jun. 30, 2011 2007 Plan Stock options Maximum	Jun. 30, 2011 2007 Plan Stock options Maximum TomoTherapy	Jun. 30, 2013 2007 Plan RSUs	Jun. 30, 2013 2007 Plan Time-based RSUs	Jun. 30, 2011 2007 Plan RSA TomoTherapy
Stock Incentive Plan
Number of stock incentive plans	3
Exercise price of stock options as a percentage of fair market value on the grant date				100.00%	85.00%	25.00%
Vesting period for first 25% vesting rights						1 year
Remainder vesting period						36 months
Annual vesting percentage																				25.00%
Percentage of the award vesting at first anniversary																			10.00%
Percentage of the award vesting at second anniversary																			20.00%
Percentage of the award vesting at third anniversary																			30.00%
Percentage of the award vesting at fourth anniversary																			40.00%
Stock options assumed (in shares)			1,539,255					1,539,000
RSAs assumed (in shares)			429,591
Exercise price, low end of range (in dollars per share)										$ 0.48
Exercise price, high end of range (in dollars per share)										$ 44.24
Remaining contractual term						6 years 2 months 1 day	5 years 6 months 25 days	5 years 1 month 17 days	5 years 11 months 8 days					1 month 6 days				3 years 4 months 24 days
Remaining vesting term		10 years																			1 year 2 months 12 days
Weighted average assumptions used for determining fair value of stock options
Risk-free interest rate (as a percent)											0.87%	0.85%	1.88%		1.15%	1.72%	2.44%
Expected life						6 years 3 months	6 years 3 months	6 years 3 months
Expected volatility (as a percent)											52.70%	52.00%	52.80%		63.20%	52.90%	54.90%