Note 4 - Acquisitions (Detail) (USD $)	3 Months Ended		12 Months Ended					1 Months Ended			1 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2010	Nov. 07, 2011	Nov. 01, 2011	Jan. 31, 2011	Dec. 31, 2011 Ideal Image [Member]	Dec. 31, 2012 Ideal Image [Member]	Nov. 30, 2011 Ideal Image [Member]	Dec. 31, 2011 Cortiva [Member]	Nov. 30, 2011 Cortiva [Member]
Business Acquisition, Cost of Acquired Entity, Purchase Price					$ 33,000,000	$ 175,000,000	$ 4,500,000		$ 162,216,000	$ 175,000,000		$ 33,000,000
Noncash or Part Noncash Acquisition, Accounts Receivable Acquired								2,300,000			2,600,000
Payments for (Proceeds from) Other Investing Activities		(1,300,000)	(3,614,000)	(3,895,000)
Prior Period Reclassification Adjustment	$ 1,300,000