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, 2013	$ 777,160	$ 330	$ 753,635	$ 3,043	$ 9,538	$ 766,546	$ 10,614
Balance, shares at Dec. 31, 2013	33,051,176	33,051,176
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	23,059			23,533	(797)	22,736	323
Distributions to noncontrolling interest	(432)						(432)
Shares issued on stock options exercised, shares		823
Share-based compensation	1,349		1,349			1,349
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt	7,499		7,499			7,499
Dividends declared, $.77 per share	(25,450)			(25,450)		(25,450)
Balance, value at Mar. 31, 2014	$ 783,185	$ 330	$ 762,483	$ 1,126	$ 8,741	$ 772,680	$ 10,505
Balance, shares at Mar. 31, 2014	33,051,999	33,051,999