Revenues Financial Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Revenue [Line Items]
Revenues	$ 520,972		$ 520,741		$ 483,712		$ 384,987		$ 445,077		$ 418,529		$ 404,883		$ 366,417		$ 1,910,412		$ 1,634,906		$ 1,672,390
Net (loss) earnings attributable to Stewart	$ 61,760		$ 34,668		$ 24,911		$ (12,157)		$ 2,159		$ 4,542		$ 5,940		$ (10,293)		$ 109,182		$ 2,348		$ (12,582)
Diluted (loss) earnings per share attributable to Stewart	$ 2.56	[1]	$ 1.45	[1]	$ 1.05	[1]	$ (0.63)	[1]	$ 0.11	[1]	$ 0.22	[1],[2]	$ 0.28	[1],[2]	$ (0.55)	[1]	$ 4.61	[1]	$ 0.12	[1]	$ (0.69)

[1] Quarterly per share data may not sum to annual totals due to rounding or effects of dilution in particular quarters but not in annual totals.

[2] The diluted earnings per share attributable to Stewart was primarily due to dilutive effects of the Convertible Senior Notes (Note 10) using the if-converted method (Note 15).