Note 6 - Product Warranty Obligations (Details) - Reconciliation of Product Warranty Liability (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reconciliation of Product Warranty Liability [Abstract]
Balance at beginning of period	$ 31,907	$ 40,207	$ 33,734	$ 36,112
Payments	(4,076)	(3,903)	(11,024)	(9,596)
Provision for warranties issued	5,764	9,352	12,028	20,340
Changes in estimates for pre-existing warranties	(1,424)	(5,500)	(2,567)	(6,700)
Balance at end of period	32,171	40,156	32,171	40,156
Balance at beginning of period	24,632	15,042	23,092	13,473
Deferred revenue on extended warranty contracts sold	1,795	2,268	4,014	4,406
Amortization of deferred revenue on extended warranty contracts	(748)	(581)	(1,427)	(1,150)
Balance at end of period	$ 25,679	$ 16,729	$ 25,679	$ 16,729