CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Retained Earnings	Cost of Common Stock in Treasury	Accumulated Other Comprehensive Income (Loss), Net	Total Shareholders' Equity	Noncontrolling Interests
Balance at Dec. 31, 2019	$ 848,636	$ 436,538	$ 463,269	$ (76,702)	$ 5,172	$ 828,277	$ 20,359
Increase (Decrease) in Shareholders' Equity
Net income	16,418		16,413			16,413	5
Other comprehensive (loss) income	12,479				12,479	12,479
Issuance of 35,027 and 25,910 common shares under stock based compensation awards for the three months ended March 31, 2021 and 2020, respectively	1,137		638	499		1,137
Cost of 155,457 and 0 shares of common stock acquired for treasury for the three months ended March 31, 2021 and 2020, respectively	0			0		0
Common stock dividend ($0.29 and $0.29 per share for the three months ended March 31, 2021 and 2020, respectively)	(7,409)		(7,409)			(7,409)
Contributions from noncontrolling interests	6,140					0	6,140
Distributions to noncontrolling interests	$ (99)					0	(99)
Issuance of common shares under stock based compensation awards (in shares)	25,910
Common stock acquired for treasury (in shares)	0
Cash dividends (in dollars per share)	$ 0.29
Balance at Mar. 31, 2020	$ 877,302	436,538	472,911	(76,203)	17,651	850,897	26,405
Balance at Dec. 31, 2020	930,670	436,538	514,176	(82,240)	18,371	886,845	43,825
Increase (Decrease) in Shareholders' Equity
Net income	28,106		28,105			28,105	1
Other comprehensive (loss) income	(11,128)				(11,128)	(11,128)
Issuance of 35,027 and 25,910 common shares under stock based compensation awards for the three months ended March 31, 2021 and 2020, respectively	1,482		844	638		1,482
Cost of 155,457 and 0 shares of common stock acquired for treasury for the three months ended March 31, 2021 and 2020, respectively	(6,621)			(6,621)		(6,621)
Common stock dividend ($0.29 and $0.29 per share for the three months ended March 31, 2021 and 2020, respectively)	(7,388)		(7,388)			(7,388)
Contributions from noncontrolling interests	887					0	887
Distributions to noncontrolling interests	$ (249)					0	(249)
Issuance of common shares under stock based compensation awards (in shares)	35,027
Common stock acquired for treasury (in shares)	155,457
Cash dividends (in dollars per share)	$ 0.29
Balance at Mar. 31, 2021	$ 935,759	$ 436,538	$ 535,737	$ (88,223)	$ 7,243	$ 891,295	$ 44,464