Note 20 - Reportable Segments - Information Concerning Principal Geographic Areas (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Net sales		$ 2,476,000	$ 2,507,000	$ 2,360,000	$ 2,047,000	$ 2,231,000	$ 2,272,000	$ 2,343,000	$ 2,265,000	$ 9,390,000	[1]	$ 9,111,000	[1]	$ 9,715,000	[1]
Long- lived assets	[2]	16,376,000				18,189,000				16,376,000		18,189,000		17,888,000
UNITED STATES
Net sales	[1]									2,625,000		2,719,000		2,275,000
Long- lived assets	[2]	6,473,000				8,241,000				6,473,000		8,241,000		7,998,000
CANADA
Net sales	[1]									282,000		244,000		311,000
Long- lived assets	[2]	142,000				144,000				142,000		144,000
MEXICO
Net sales	[1]									50,000		37,000		35,000
Long- lived assets	[2]	134,000				135,000				134,000		135,000		50,000
North America [Member]
Net sales	[1]									2,957,000		3,000,000		2,621,000
Long- lived assets	[2]	6,749,000				8,520,000				6,749,000		8,520,000		8,048,000
JAPAN
Net sales	[1]									450,000		440,000		608,000
Long- lived assets	[2]	1,008,000				1,160,000				1,008,000		1,160,000		1,311,000
TAIWAN, PROVINCE OF CHINA
Net sales	[1]									840,000		841,000		1,092,000
Long- lived assets	[2]	2,347,000				2,301,000				2,347,000		2,301,000		2,005,000
CHINA
Net sales	[1]									2,083,000		1,869,000		1,893,000
Long- lived assets	[2]	1,140,000				1,036,000				1,140,000		1,036,000		1,115,000
KOREA, REPUBLIC OF
Net sales	[1]									1,444,000		1,501,000		1,882,000
Long- lived assets	[2]	3,413,000				3,552,000				3,413,000		3,552,000		3,595,000
Other Asia Pacific [Member]
Net sales	[1]									363,000		331,000		308,000
Long- lived assets	[2]	167,000				98,000				167,000		98,000		109,000
Asia Pacific [Member]
Net sales	[1]									5,180,000		4,982,000		5,783,000
Long- lived assets	[2]	8,075,000				8,147,000				8,075,000		8,147,000		8,135,000
GERMANY
Net sales	[1]									363,000		326,000		397,000
Long- lived assets	[2]	154,000				189,000				154,000		189,000		217,000
FRANCE
Net sales	[1]									83,000		90,000		81,000
Long- lived assets	[2]	266,000				263,000				266,000		263,000		277,000
UNITED KINGDOM
Net sales	[1]									182,000		164,000		187,000
Long- lived assets	[2]	41,000				47,000				41,000		47,000		47,000
Other Europe [Member]
Net sales	[1]									352,000		311,000		369,000
Long- lived assets	[2]	1,047,000				987,000				1,047,000		987,000		1,109,000
Europe [Member]
Net sales	[1]									980,000		891,000		1,034,000
Long- lived assets	[2]	1,508,000				1,486,000				1,508,000		1,486,000		1,650,000
All Other [Member]
Net sales	[1]									273,000		238,000		277,000
Long- lived assets	[2]	$ 44,000				$ 36,000				$ 44,000		$ 36,000		$ 55,000

[1] Net sales are attributed to countries based on location of customer.

[2] Long-lived assets primarily include investments, plant and equipment, goodwill and other intangible assets. In 2014 and 2015, assets in the U.S. include the investment in Dow Corning.