Consolidated Statement of Changes in Equity (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]
Balance at at Dec. 31, 2010	$ 190,537	$ 11,492	$ 38,275	$ 146,802	$ (12,753)	$ 6,721
Net income	48,223	0	0	45,892	0	2,331
Other Comprehensive Income (Loss), Net of Tax	(17,289)	0	0	0	(16,214)	(1,075)
Dividends Common Stock	(11,984)	0	0	(11,984)	0	0
Dividends paid to noncontrolling interest	(1,000)	0	0	0	0	(1,000)
Stock offering, net of related expenses	48,143	1,265	46,878	0	0	0
Shares issued upon exercise of stock options and other	858	47	811	0	0	0
Shares issued for empoyee stock purchase plan	247	8	239	0	0	0
Equity-based compensation plans	3,513	100	3,413	0	0	0
Excess tax benefit from stock option exercises	109	0	109	0	0	0
Balance at at Dec. 31, 2011	261,357	12,912	89,725	180,710	(28,967)	6,977
Net income	50,240	0	0	47,405	0	2,835
Other Comprehensive Income (Loss), Net of Tax	(13,025)	0	0	0	(12,888)	(137)
Dividends Common Stock	(12,725)	0	0	(12,725)	0	0
Dividends paid to noncontrolling interest	(1,099)	0	0	0	0	(1,099)
Stock offering, net of related expenses	0	0	0	0	0	0
Shares issued upon exercise of stock options and other	(1,194)	102	(1,296)	0	0	0
Shares issued for empoyee stock purchase plan	270	7	263	0	0	0
Equity-based compensation plans	3,807	74	3,733	0	0	0
Excess tax benefit from stock option exercises	2,045	0	2,045	0	0	0
Balance at at Dec. 31, 2012	289,676	13,095	94,470	215,390	(41,855)	8,576
Net income	58,851	0	0	56,339	0	2,512
Other Comprehensive Income (Loss), Net of Tax	5,849	0	0	0	7,155	(1,306)
Dividends Common Stock	(13,109)	0	0	(13,109)	0	0
Dividends paid to noncontrolling interest	(905)	0	0	0	0	(905)
Stock offering, net of related expenses	0	0	0	0	0	0
Shares issued upon exercise of stock options and other	(644)	24	(668)	0	0	0
Shares issued for empoyee stock purchase plan	337	6	331	0	0	0
Equity-based compensation plans	4,161	71	4,090	0	0	0
Excess tax benefit from stock option exercises	815	0	815	0	0	0
Balance at at Dec. 31, 2013	$ 345,031	$ 13,196	$ 99,038	$ 258,620	$ (34,700)	$ 8,877