COMPUTATION OF EARNINGS (LOSS) PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Information related to EPS computation
Net income (loss) allocated to common shareholders	$ 1,572	$ 8,438	$ 24,953	$ 23,733
Basic:
Weighted-average common shares outstanding (in shares)	27,466	27,017	27,335	26,972
Basic (in dollars per share)	$ 0.05	$ 0.26	$ 0.75	$ 0.72
Diluted:
Weighted-average shares outstanding used in basic calculation (in shares)	27,466	27,017	27,335	26,972
Dilutive effect of options (in shares)	112	235	114	260
Dilutive effect of unvested restricted stock (in shares)	277	71	306	67
Weighted-average common stock and common stock equivalents (in shares)	27,855	27,323	27,755	27,299
Diluted (in dollars per share)	$ 0.05	$ 0.25	$ 0.74	$ 0.72
Common Stock
Information related to EPS computation
Net income (loss) allocated to common shareholders	1,298	6,945	20,581	19,529
Common Stock \| Continuing Operations
Information related to EPS computation
Net income (loss) allocated to common shareholders	1,298	6,875	19,005	19,832
Basic:
Basic (in dollars per share)	$ 0.05	$ 0.25	$ 0.70	$ 0.74
Diluted:
Diluted (in dollars per share)	$ 0.05	$ 0.25	$ 0.68	$ 0.73
Common Stock \| Discontinued Operations
Information related to EPS computation
Net income (loss) allocated to common shareholders		70	1,576	(303)
Basic:
Basic (in dollars per share)	$ 0.00	$ 0.01	$ 0.05	$ (0.02)
Diluted:
Diluted (in dollars per share)	$ 0.00	$ 0.00	$ 0.06	$ (0.01)
Series A Preferred Stock
Information related to EPS computation
Series A 3% Redeemable Convertible Preferred Stock, dividend rate (as a percent)			3.00%		3.00%
Net income (loss) allocated to common shareholders	1,131	2,313	6,918	6,638
Diluted:
Stock issuable upon conversion of the Series A Preferred Stock (in shares)	5,806	5,806	5,806	5,806
Stock awards excluded from calculation as their effect would be anti-dilutive (in shares)	1,325	2,105	1,026	2,067
Series A Preferred Stock \| Continuing Operations
Information related to EPS computation
Net income (loss) allocated to common shareholders	1,131	2,298	6,583	6,703
Series A Preferred Stock \| Discontinued Operations
Information related to EPS computation
Net income (loss) allocated to common shareholders		$ 15	$ 335	$ (65)

Number of shares issuable upon conversion of all outstanding shares of convertible preferred stock.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of non-vested restricted stock arrangements.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The earnings attributable to each security on the basis that all of the earnings for the period had been distributed (to the extent that each security may share in earnings). This is the earnings amount which reflects the participation rights in undistributed earnings of each security.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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