Note 7 - Segment Reporting - Net Sales by Products and Services (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Net sales	$ 475,915	$ 470,353
Domestic [Member]
Net sales	376,030	356,498
International [Member]
Net sales	99,885	113,855
Residential Power Products [Member]
Net sales	257,619	217,830
Residential Power Products [Member] \| Domestic [Member]
Net sales	243,830	204,259
Residential Power Products [Member] \| International [Member]
Net sales	13,789	13,571
Commercial and Industrial Power Products [Member]
Net sales	172,066	209,124
Commercial and Industrial Power Products [Member] \| Domestic [Member]
Net sales	95,827	120,825
Commercial and Industrial Power Products [Member] \| International [Member]
Net sales	76,239	88,299
Other Products and Services [Member]
Net sales	46,230	43,399
Other Products and Services [Member] \| Domestic [Member]
Net sales	36,373	31,414
Other Products and Services [Member] \| International [Member]
Net sales	$ 9,857	$ 11,985

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details