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, 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 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 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
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net Income	93,313		93,079		234
Other comprehensive loss	(6,020)			(6,165)	145
Stock issued	17,007	17,007
Stock purchased	(11,632)	(11,272)			(360)
Dividends declared	(49,925)	16,554	(66,479)
Balance at Dec. 31, 2016	$ 730,889	$ 348,771	$ 575,380	$ (196,600)	$ 3,338