CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Common Stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock	Noncontrolling interests
Balances at beginning of period at Dec. 31, 2020	$ 1,012,406	$ 27,080	$ 274,857	$ 688,819	$ 17,022	$ (2,666)	$ 7,294
Increase (Decrease) in Stockholders' Equity
Net income attributable to Stewart	237,718			237,718
Dividends on common stock	(27,009)			(27,009)
Stock-based compensation	8,494	139	8,355
Stock repurchases	(2,145)	(41)	(2,104)
Stock option and employee stock purchase plan exercises	2,715	64	2,651
Purchase of remaining interest in consolidated subsidiary	(5,616)		(4,744)				(872)
Change in net unrealized gains and losses on investments, net of taxes	(10,330)				(10,330)
Reclassification adjustment for realized gains and losses on investments, net of taxes	(918)				(918)
Foreign currency translation adjustments, net of taxes	(997)				(997)
Net income attributable to noncontrolling interests	11,639						11,639
Distributions to noncontrolling interests	(11,683)						(11,683)
Net effect of other changes in ownership	2,426						2,426
Balances at end of period at Sep. 30, 2021	1,216,700	27,242	279,015	899,528	4,777	(2,666)	8,804
Balances at beginning of period at Jun. 30, 2021	1,136,073	27,177	274,074	819,834	11,558	(2,666)	6,096
Increase (Decrease) in Stockholders' Equity
Net income attributable to Stewart	88,663			88,663
Dividends on common stock	(8,969)			(8,969)
Stock-based compensation	2,615	8	2,607
Stock repurchases	(143)	(2)	(141)
Stock option exercises	2,534	59	2,475
Change in net unrealized gains and losses on investments, net of taxes	(2,183)				(2,183)
Reclassification adjustment for realized gains and losses on investments, net of taxes	(355)				(355)
Foreign currency translation adjustments, net of taxes	(4,243)				(4,243)
Net income attributable to noncontrolling interests	4,732						4,732
Distributions to noncontrolling interests	(4,430)						(4,430)
Net effect of other changes in ownership	2,406						2,406
Balances at end of period at Sep. 30, 2021	1,216,700	27,242	279,015	899,528	4,777	(2,666)	8,804
Balances at beginning of period at Dec. 31, 2021	1,294,735	27,246	282,376	974,800	253	(2,666)	12,726
Increase (Decrease) in Stockholders' Equity
Net income attributable to Stewart	148,991			148,991
Dividends on common stock	(32,853)			(32,853)
Stock-based compensation	9,239	155	9,084
Stock repurchases	(3,168)	(49)	(3,119)
Stock option and employee stock purchase plan exercises	5,799	124	5,675
Purchase of remaining interest in consolidated subsidiary	(72)		0				(72)
Change in net unrealized gains and losses on investments, net of taxes	(41,513)				(41,513)
Reclassification adjustment for realized gains and losses on investments, net of taxes	(687)				(687)
Foreign currency translation adjustments, net of taxes	(22,861)				(22,861)
Net income attributable to noncontrolling interests	14,534						14,534
Distributions to noncontrolling interests	(14,863)						(14,863)
Net effect of other changes in ownership	220						220
Balances at end of period at Sep. 30, 2022	1,357,501	27,476	294,016	1,090,938	(64,808)	(2,666)	12,545
Balances at beginning of period at Jun. 30, 2022	1,359,821	27,390	288,834	1,073,788	(40,202)	(2,666)	12,677
Increase (Decrease) in Stockholders' Equity
Net income attributable to Stewart	29,434			29,434
Dividends on common stock	(12,284)			(12,284)
Stock-based compensation	2,799	29	2,770
Stock repurchases	(617)	(12)	(605)
Stock option and employee stock purchase plan exercises	3,086	69	3,017
Purchase of remaining interest in consolidated subsidiary	(72)		0				(72)
Change in net unrealized gains and losses on investments, net of taxes	(8,921)				(8,921)
Reclassification adjustment for realized gains and losses on investments, net of taxes	(385)				(385)
Foreign currency translation adjustments, net of taxes	(15,300)				(15,300)
Net income attributable to noncontrolling interests	5,294						5,294
Distributions to noncontrolling interests	(5,380)						(5,380)
Net effect of other changes in ownership	26						26
Balances at end of period at Sep. 30, 2022	$ 1,357,501	$ 27,476	$ 294,016	$ 1,090,938	$ (64,808)	$ (2,666)	$ 12,545