Fair Value Measurements (Narrative) (Detail) (USD $)	3 Months Ended						1 Months Ended
	Jun. 30, 2013		Dec. 31, 2012		Jun. 30, 2013 AxoGen Note Receivable [Member]	Dec. 31, 2012 AxoGen Note Receivable [Member]	Apr. 30, 2013 Avinger Note Receivable [Member]
Embedded Derivative, Fair Value of Embedded Derivative Asset					$ 1,000,000	$ 600,000
Restricted investment	20,000,000	[1]	20,000,000	[2]
Transfers from level 1 to level 2, amount	0		0
Transfers from level 2 to level 1, amount	$ 0		$ 0
Fair value inputs, discount rate (in Percent)	35.00%						18.50%
Earnings before interest, taxes, depreciation and amortization multiple	17.5
Terminal value, sales multiple	3.0

[1] unaudited

[2] Note 1