Consolidated Statements of Income - USD ($) shares in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Net Sales (Note 1)	[1]	$ 2,325,768,000	$ 2,773,270,000	$ 2,345,966,000
Cost of Sales		2,048,170,000	2,346,201,000	1,950,156,000
Gross Profit		277,598,000	427,069,000	395,810,000
Operating Expenses:
Selling (Note 1)		48,367,000	59,030,000	59,186,000
Administrative (Note 1)		93,202,000	102,177,000	92,906,000
Research, development and technical services (Note 1)		59,039,000	66,633,000	62,689,000
Deferred compensation (income) expense (Note 12)		4,371,000	(9,393,000)	6,895,000
Total Operating expenses		204,979,000	218,447,000	221,676,000
Goodwill and other intangibles impairment (Note 4)		2,038,000	978,000
Business restructuring, assets impairment and loss on asset disposition (Note 22)	[2]	11,968,000	308,000	3,353,000
Operating Income		58,613,000	207,336,000	170,781,000
Other Income (Expense):
Interest, net (Note 6)		(12,103,000)	(9,809,000)	(5,753,000)
Other, net (Note 8)		1,881,000	(8,824,000)	7,509,000
Nonoperating Income (Expense), Total		(10,222,000)	(18,633,000)	1,756,000
Income Before Provision for Income Taxes		48,391,000	188,703,000	172,537,000
Provision for Income Taxes (Note 9)		8,187,000	41,550,000	34,642,000
Net Income		40,204,000	147,153,000	137,895,000
Net Income Attributable to Noncontrolling Interest (Note 1)				(91,000)
Net Income Attributable to Stepan Company		$ 40,204,000	$ 147,153,000	$ 137,804,000
Net Income Per Common Share Attributable to Stepan Company (Note 18):
Basic		$ 1.77	$ 6.46	$ 6.01
Diluted		$ 1.75	$ 6.38	$ 5.92
Shares Used to Compute Net Income Per Common Share Attributable to Stepan Company (Note 18):
Basic		22,777	22,781	22,922
Diluted		22,946	23,064	23,287

[1] Includes net property, plant and equipment, goodwill and other intangible assets.

[2] See Note 22, Business Restructuring, Assets Impairment and Asset Disposition, of the notes to the Company’s consolidated financial statements (included in Item 8 of this Form 10-K) regarding business restructuring and asset disposition costs.