Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Net Sales (Note 1)	[1]	$ 1,776,167	$ 1,927,213	$ 1,880,786
Cost of Sales		1,467,926	1,677,650	1,599,101
Gross Profit		308,241	249,563	281,685
Operating Expenses:
Selling (Note 1)		55,522	54,763	53,229
Administrative (Note 1)	[2]	76,048	66,549	61,958
Research, development and technical services (Note 1)		50,243	45,451	46,809
Deferred compensation expense (income) (Note 1)	[2]	6,500	(11,903)	9,496
Total Operating expenses		188,313	154,860	171,492
Gain on sale of product line		2,862
Business restructuring and asset impairments (Note 22)			(4,009)	(1,040)
Operating Income		122,790	90,694	109,153
Other Income (Expense):
Interest, net (Note 6)		(14,533)	(11,441)	(10,358)
Loss from equity in joint ventures (Notes 1 and 25)		(6,985)	(5,008)	(5,336)
Other, net (Note 8)		1,584	1,290	2,171
Nonoperating Income (Expense), Total		(19,934)	(15,159)	(13,523)
Income Before Provision for Income Taxes		102,856	75,535	95,630
Provision for Income Taxes (Note 9)		26,819	18,454	23,293
Net Income		76,037	57,081	72,337
Net (Income) Loss Attributable to Noncontrolling Interests (Note 1)		(69)	20	491
Net Income Attributable to Stepan Company		$ 75,968	$ 57,101	$ 72,828
Net Income Per Common Share Attributable to Stepan Company (Note 18):
Basic		$ 3.34	$ 2.51	$ 3.22
Diluted		$ 3.32	$ 2.49	$ 3.18
Shares Used to Compute Net Income Per Common Share Attributable to Stepan Company (Note 18):
Basic		22,730	22,758	22,621
Diluted		22,858	22,917	22,924

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

[2] In 2014 and 2013, deferred compensation expense (income) was included in administrative expenses. The 2014 and 2013 amounts have been changed to conform to the current year presentation.