Consolidated Statements of Changes in Shareholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Balance at Dec. 31, 2012	$ 600,216	$ 310,008	$ 453,770	$ (166,814)	$ 3,252
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net Income	81,274		81,063		211
Other comprehensive income (loss)	26,285			26,451	(166)
Stock issued	13,327	12,839			488
Stock purchased	(12,920)	(12,772)			(148)
Dividends declared	(37,401)	7,692	(45,093)
Balance at Dec. 31, 2013	670,781	317,767	489,740	(140,363)	3,637
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net Income	87,686		87,428		258
Other comprehensive income (loss)	(12,104)			(11,830)	$ (274)
Stock issued	14,492	14,492
Stock purchased	(15,378)	$ (15,060)			$ (318)
Dividends declared	(63,496)		(63,496)
Balance at Dec. 31, 2014	681,981	$ 317,199	513,672	(152,193)	3,303
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net Income	91,332		91,068		264
Other comprehensive income (loss)	(38,782)			(38,242)	(540)
Stock issued	16,124	15,723			401
Stock purchased	(14,474)	(14,365)			(109)
Dividends declared	(48,035)	7,925	(55,960)
Balance at Dec. 31, 2015	$ 688,146	$ 326,482	$ 548,780	$ (190,435)	$ 3,319