Equity and Noncontrolling Interest (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Beginning Balance	$ 364,710	$ 312,357	$ 344,696	$ 289,676
Net Income	16,119	13,305	45,370	44,171
Amounts reported in other comprehensive income (loss)	(10,072)	1,759	(6,760)	(2,602)
Dividends, Common Stock	(3,981)	(3,298)	(11,262)	(9,810)
Distributions to Noncontrolling Affiliate Shareholders	(1,149)	(30)	(1,806)	(30)
Acqusition of Noncontrolling Interest	155	0	(7,422)	0
Share Issuance and Equity-Based Compensation Plans	1,066	387	3,765	2,623
Excess Tax Benefit From Stock Option Exercises	163	363	430	815
Ending Balance	367,011	324,843	367,011	324,843
Common Stock Member
Beginning Balance	13,242	13,168	13,196	13,095
Net Income	0	0	0	0
Amounts reported in other comprehensive income (loss)	0	0	0	0
Dividends, Common Stock	0	0	0	0
Distributions to Noncontrolling Affiliate Shareholders	0	0	0	0
Acqusition of Noncontrolling Interest	0	0	0	0
Share Issuance and Equity-Based Compensation Plans	27	19	73	92
Excess Tax Benefit From Stock Option Exercises	0	0	0	0
Ending Balance	13,269	13,187	13,269	13,187
Additional Paid-in Capital [Member]
Beginning Balance	95,508	97,085	99,038	94,470
Net Income	0	0	0	0
Amounts reported in other comprehensive income (loss)	0	0	0	0
Dividends, Common Stock	0	0	0	0
Distributions to Noncontrolling Affiliate Shareholders	0	0	0	0
Acqusition of Noncontrolling Interest	7	0	(6,443)	0
Share Issuance and Equity-Based Compensation Plans	1,039	368	3,692	2,531
Excess Tax Benefit From Stock Option Exercises	163	363	430	815
Ending Balance	96,717	97,816	96,717	97,816
Retained Earnings [Member]
Beginning Balance	279,161	238,580	258,285	215,390
Net Income	15,696	12,551	43,853	42,253
Amounts reported in other comprehensive income (loss)	0	0	0	0
Dividends, Common Stock	(3,981)	(3,298)	(11,262)	(9,810)
Distributions to Noncontrolling Affiliate Shareholders	0	0	0	0
Acqusition of Noncontrolling Interest	0	0	0	0
Share Issuance and Equity-Based Compensation Plans	0	0	0	0
Excess Tax Benefit From Stock Option Exercises	0	0	0	0
Ending Balance	290,876	247,833	290,876	247,833
Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance	(31,587)	(45,252)	(34,700)	(41,855)
Net Income	0	0	0	0
Amounts reported in other comprehensive income (loss)	(9,826)	2,014	(6,713)	(1,383)
Dividends, Common Stock	0	0	0	0
Distributions to Noncontrolling Affiliate Shareholders	0	0	0	0
Acqusition of Noncontrolling Interest	0	0	0	0
Share Issuance and Equity-Based Compensation Plans	0	0	0	0
Excess Tax Benefit From Stock Option Exercises	0	0	0	0
Ending Balance	(41,413)	(43,238)	(41,413)	(43,238)
Noncontrolling Interest [Member]
Beginning Balance	8,386	8,776	8,877	8,576
Net Income	423	754	1,517	1,918
Amounts reported in other comprehensive income (loss)	(246)	(255)	(47)	(1,219)
Dividends, Common Stock	0	0	0	0
Distributions to Noncontrolling Affiliate Shareholders	(1,149)	(30)	(1,806)	(30)
Acqusition of Noncontrolling Interest	148	0	(979)	0
Share Issuance and Equity-Based Compensation Plans	0	0	0	0
Excess Tax Benefit From Stock Option Exercises	0	0	0	0
Ending Balance	$ 7,562	$ 9,245	$ 7,562	$ 9,245