Equity (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Common Shares [Member]	Jun. 30, 2012 Common Shares [Member]	Jun. 30, 2014 Additional Paid-In Capital [Member]	Jun. 30, 2012 Additional Paid-In Capital [Member]	Jun. 30, 2014 Retained Earnings [Member]	Jun. 30, 2012 Retained Earnings [Member]	Jun. 30, 2014 Accumulated Other Comprehensive Income (Loss) [Member]	Jun. 30, 2012 Accumulated Other Comprehensive Income (Loss) [Member]	Jun. 30, 2014 Treasury Stock [Member]	Jun. 30, 2012 Treasury Stock [Member]	Jun. 30, 2014 Non-Controlling Interests [Member]	Jun. 30, 2012 Non-Controlling Interests [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 169,389		$ 1,203		$ 0		$ 415,930		$ (8,626)		$ (245,184)		$ 6,066
Stock options exercised			0		0				0		0				0
Stock based-awards			10,646		0		1,242		0		0		9,404		0
Tax benefit of stock-based awards issued			1,449		0		1,449		0		0		0		0
Repurchase of common shares			(125,294)		0		0		0		0		(125,294)		0
Dividends paid			(44,936)		0		0		(44,936)		0		0		0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders			(394)			0		0		0		0		0		(394)
Amortization of deferred pension costs, net of tax			172		0		0		0		172		0		0
Net income (loss)	64,096	59,942	125,249	116,674	0		0		124,798		0		0
Net income (loss) attributable to non-controlling interest	362	266	451	482
Ending balance	$ 136,281		$ 136,281		$ 1,203		$ 2,691		$ 495,792		$ (8,454)		$ (361,074)		$ 6,123