Consolidated Statements of Changes in Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Beginning Balance (in shares) at Dec. 31, 2013		63,096
Beginning Balance at Dec. 31, 2013	$ 1,025,043	$ 126,193	$ 196,605	$ 691,547	$ 9,568	$ 1,130
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	45,362			45,362
Other comprehensive income	122				122
Dividends declared	(31,473)			(31,473)
Shares repurchased and retired (in shares)		(277)
Shares repurchased and retired	(9,448)	$ (555)		(8,893)
Share-based compensation expense, exercises and other (shares)		247
Share-based compensation expense, exercises and other	3,604	$ 495	3,109
Purchase of noncontrolling interest	(1,825)		(695)			(1,130)
Ending Balance (in shares) at Jun. 30, 2014		63,066
Ending Balance at Jun. 30, 2014	$ 1,031,385	$ 126,133	199,019	696,543	9,690	0
Beginning Balance (in shares) at Dec. 31, 2014	63,070	63,070
Beginning Balance at Dec. 31, 2014	$ 990,838	$ 126,140	202,934	685,765	(24,001)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	43,166			43,166
Other comprehensive income	(20,787)				(20,787)
Dividends declared	$ (31,779)			(31,779)
Shares repurchased and retired (in shares)	(220)	(220)
Shares repurchased and retired	$ (7,440)	$ (440)		(7,000)
Share-based compensation expense, exercises and other (shares)		168
Share-based compensation expense, exercises and other	$ 3,129	$ 336	2,793
Ending Balance (in shares) at Jun. 30, 2015	63,018	63,018
Ending Balance at Jun. 30, 2015	$ 977,127	$ 126,036	$ 205,727	$ 690,152	$ (44,788)	$ 0