Business Segments (Tables)

6 Months Ended

Jun. 30, 2013

Segment Reporting Measurement Disclosures [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]

		Three Months Ended				Six Months Ended
		June 30,				June 30,
		2013		2012		2013		2012
Metalworking Process Chemicals
	Net sales	$	172,241	$	165,011	$	337,177	$	330,986
	Operating income for reportable segment		34,121		30,649		66,148		61,624
Coatings
	Net sales		12,185		10,950		22,931		21,473
	Operating income for reportable segment		3,616		2,799		6,122		5,312
Other Chemical Products
	Net sales		420		836		931		1,976
	Operating (loss) income for reportable segment		(33)		53		(54)		195
Total
	Net sales		184,846		176,797		361,039		354,435
	Operating income for reportable segments		37,704		33,501		72,216		67,131
Non-operating expenses			(17,027)		(15,799)		(33,249)		(31,981)
Amortization expense			(884)		(719)		(1,763)		(1,465)
Consolidated operating income			19,793		16,983		37,204		33,685
Interest expense			(762)		(1,151)		(1,506)		(2,325)
Interest income			229		137		398		260
Other income (expense), net			2,301		(134)		2,647		207
Consolidated income before taxes and equity in net income of associated companies		$	21,561	$	15,835	$	38,743	$	31,827