Equity and Noncontrolling Interest (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Beginning Balance	$ 344,696	$ 289,676
Net Income	13,309	14,191
Amounts reported in other comprehensive income (loss)	1,889	(25)
Dividends, Common Stock	(3,308)	(3,219)
Share Issuance and Equity-Based Compensation Plans	1,183	981
Excess Tax Benefit From Stock Option Exercises	239	369
Ending Balance	358,008	301,973
Common Stock Member
Beginning Balance	13,196	13,095
Net Income	0	0
Amounts reported in other comprehensive income (loss)	0	0
Dividends, Common Stock	0	0
Share Issuance and Equity-Based Compensation Plans	31	45
Excess Tax Benefit From Stock Option Exercises	0	0
Ending Balance	13,227	13,140
Additional Paid-in Capital [Member]
Beginning Balance	99,038	94,470
Net Income	0	0
Amounts reported in other comprehensive income (loss)	0	0
Dividends, Common Stock	0	0
Share Issuance and Equity-Based Compensation Plans	1,152	936
Excess Tax Benefit From Stock Option Exercises	239	369
Ending Balance	100,429	95,775
Retained Earnings [Member]
Beginning Balance	258,285	215,390
Net Income	12,730	13,619
Amounts reported in other comprehensive income (loss)	0	0
Dividends, Common Stock	(3,308)	(3,219)
Share Issuance and Equity-Based Compensation Plans	0	0
Excess Tax Benefit From Stock Option Exercises	0	0
Ending Balance	267,707	225,790
Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance	(34,700)	(41,855)
Net Income	0	0
Amounts reported in other comprehensive income (loss)	1,685	108
Dividends, Common Stock	0	0
Share Issuance and Equity-Based Compensation Plans	0	0
Excess Tax Benefit From Stock Option Exercises	0	0
Ending Balance	(33,015)	(41,747)
Noncontrolling Interest [Member]
Beginning Balance	8,877	8,576
Net Income	579	572
Amounts reported in other comprehensive income (loss)	204	(133)
Dividends, Common Stock	0	0
Share Issuance and Equity-Based Compensation Plans	0	0
Excess Tax Benefit From Stock Option Exercises	0	0
Ending Balance	$ 9,660	$ 9,015