Consolidated Statement Of Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Cumulative Dividends In Excess Of Net Income [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Parent [Member]	Noncontrolling Interest [Member]
Balance, value at Dec. 31, 2014	$ 1,049,933	$ 375	$ 1,033,896	$ (569)	$ 6,223	$ 1,039,925	$ 10,008
Balance, shares at Dec. 31, 2014	37,485,902	37,485,902
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	27,610			29,683	(2,403)	27,280	330
Distributions to noncontrolling interest	(436)						(436)
Equity Issuance Costs	(200)		(200)			(200)
Shares issued on stock options exercised, shares		80,319
Stock Issued During Period, Value, Stock Options Exercised	1	1				1
Share-based compensation	1,464		1,464			1,464
Dividends declared, $1.54 per share	(31,931)			(31,931)		(31,931)
Balance, value at Mar. 31, 2015	$ 1,046,441	$ 376	$ 1,035,160	$ (2,817)	$ 3,820	$ 1,036,539	$ 9,902
Balance, shares at Mar. 31, 2015	37,566,221	37,566,221