Consolidated Condensed Statements of Stockholders Equity (Unaudited) (USD $) In Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Total
Balance at Dec. 31, 2009	$ 219	$ 76,477	$ 196,480	$ 1,731	$ 274,907
Balance (in Shares) at Dec. 31, 2009	21,885
Net income			14,532		14,532
Issuance of comm on stock from share-based payment arrangement exercises		234			234
Issuance of comm on stock from share-based payment arrangement exercises (in Shares)	49
Tax benefits from share-based payment arrangement exercises		273			273
Share-based payment arrangement compensation expense		801			801
Dividends on common stock			(438)		(438)
Income before income taxes attributable to noncontrolling interest				365	365
Noncontrolling interest distributions and other, net				(158)	(158)
Balance at Sep. 30, 2010	219	77,785	210,574	1,938	290,516
Balance (in Shares) at Sep. 30, 2010	21,934
Net income			5,210		5,210
Issuance of comm on stock from share-based payment arrangement exercises	1	68			69
Issuance of comm on stock from share-based payment arrangement exercises (in Shares)	16
Tax benefits from share-based payment arrangement exercises		112			112
Share-based payment arrangement compensation expense		463			463
Dividends on common stock			(439)		(439)
Income before income taxes attributable to noncontrolling interest				266	266
Noncontrolling interest distributions and other, net				(293)	(293)
Balance at Dec. 31, 2010	220	78,428	215,345	1,911	295,904
Balance (in Shares) at Dec. 31, 2010	21,950
Net income			16,622		16,622
Issuance of comm on stock from share-based payment arrangement exercises		137			137
Issuance of comm on stock from share-based payment arrangement exercises (in Shares)	27
Issuance of common stock from vesting of performance unit awards (in Shares)	8
Tax benefits from share-based payment arrangement exercises		164			164
Share-based payment arrangement compensation expense		930			930
Dividends on common stock			(1,318)		(1,318)
Income before income taxes attributable to noncontrolling interest				708	708
Noncontrolling interest distributions and other, net				(13)	(13)
Balance at Sep. 30, 2011	$ 220	$ 79,659	$ 230,649	$ 2,606	$ 313,134
Balance (in Shares) at Sep. 30, 2011	21,985