Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Net Sales		$ 445,897	$ 460,451
Cost of Sales		352,398	384,009
Gross Profit		93,499	76,442
Operating Expenses:
Selling		13,690	12,997
Administrative	[1]	18,700	17,762
Research, development and technical services		13,782	11,790
Deferred compensation expense	[1]	2,720	1,577
Total Operating expenses		48,892	44,126
Gain on sale of product line			2,862
Operating Income		44,607	35,178
Other Income (Expense):
Interest, net		(3,614)	(4,054)
Loss from equity in joint ventures (Note 15)			(1,240)
Other, net (Note 13)		(525)	652
Nonoperating Income (Expense), Total		(4,139)	(4,642)
Income Before Provision for Income Taxes		40,468	30,536
Provision for Income Taxes		12,811	9,250
Net Income		27,657	21,286
Net Income Attributable to Noncontrolling Interests (Note 2)		(3)	(16)
Net Income Attributable to Stepan Company		$ 27,654	$ 21,270
Net Income Per Common Share Attributable to Stepan Company (Note 9):
Basic		$ 1.22	$ 0.94
Diluted		$ 1.21	$ 0.93
Shares Used to Compute Net Income Per Common Share Attributable to Stepan Company (Note 9):
Basic		22,733	22,718
Diluted		22,882	22,827
Dividends Declared Per Common Share		$ 0.19	$ 0.18

[1] In the first quarter of 2015, deferred compensation expense was included in administrative expenses. The 2015 amounts have been classified separately to conform to the current year presentation