Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Consolidated Statements of Comprehensive Income [Abstract]
Net Income	$ 79,687	$ 72,602	$ 65,591
Other Comprehensive Income (Loss):
Foreign currency translation adjustments	6,101	(12,523)	2,585
Defined benefit pension plans:
Net actuarial loss arising in period (net of taxes of $2,568, $3,617, $2,349 for 2012, 2011 and 2010, respectively)	(5,387)	(5,259)	(3,618)
Amortization of prior service cost included in pension expense (net of taxes of $5, $6, $6 for 2012, 2011 and 2010, respectively)	13	13	13
Amortization of actuarial loss included in pension expense (net of taxes of $1,371, $1,154, $866 for 2012, 2011 and 2010, respectively)	2,261	1,913	1,479
Amortization of transition obligation included in pension expense (net of taxes of $5, $8, $8 for 2012, 2011 and 2010, respectively)	13	19	19
Net defined benefit pension plan activity	(3,100)	(3,314)	(2,107)
Cash flow hedges:
Gains (losses) arising in period (net of taxes of $16 in 2012 and $12 in 2011, respectively)	116	(1)
Reclassifications to income in period (net of taxes of $8 in 2012)	19
Net cash flow hedge activity	135	(1)
Other Comprehensive Income (Loss)	3,136	(15,838)	478
Comprehensive Income	82,823	56,764	66,069
Less: Comprehensive Income Attributable to Noncontrolling Interests	(389)	(674)	(348)
Comprehensive Income Attributable to Stepan Company	$ 82,434	$ 56,090	$ 65,721