Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Statement [Abstract]
Net Sales	$ 751,633	$ 595,511	$ 1,426,909	$ 1,133,251
Cost of Sales	620,019	483,830	1,186,076	912,590
Gross Profit	131,614	111,681	240,833	220,661
Operating Expenses:
Selling	15,552	14,990	30,829	29,494
Administrative	24,079	23,974	45,651	46,612
Research, development and technical services	16,690	14,988	33,163	30,137
Deferred compensation (income) expense	(3,406)	958	(10,907)	3,652
Total Operating expenses	52,915	54,910	98,736	109,895
Goodwill impairment (Note 18)	(978)		(978)
Business restructuring expenses (Note 16)	(81)	(114)	(133)	(195)
Operating Income	77,640	56,657	140,986	110,571
Other Income (Expense):
Interest, net	(2,727)	(1,567)	(5,033)	(3,091)
Other, net (Note 15)	(5,369)	2,758	(7,019)	3,504
Nonoperating Income (Expense), Total	(8,096)	1,191	(12,052)	413
Income Before Provision for Income Taxes	69,544	57,848	128,934	110,984
Provision for Income Taxes	17,418	14,545	31,999	27,070
Net Income	52,126	43,303	96,935	83,914
Less: Net Income Attributable to Noncontrolling Interest		(25)		(25)
Net Income Attributable to Stepan Company	$ 52,126	$ 43,278	$ 96,935	$ 83,889
Net Income Per Common Share Attributable to Stepan Company (Note 10):
Basic	$ 2.29	$ 1.89	$ 4.24	$ 3.65
Diluted	$ 2.26	$ 1.85	$ 4.19	$ 3.59
Shares Used to Compute Net Income Per Common Share Attributable to Stepan Company (Note 10):
Basic	22,792	22,952	22,842	22,963
Diluted	23,055	23,345	23,115	23,338