Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			12 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2011
Income Taxes
Research and development tax credit refund recorded for the Minnesota tax return	$ 136
Research and development tax credit refunds for the Minnesota tax return				69
Research and development tax credit refunds		$ 1,077	$ 730