Stock Based Compensation (Details Textual) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2011 Y	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Additional (Textual) [Abstract]
Shares authorized under Stock incentive plan	11,500,000
Share available under stock incentive plans	1,900,000
Matching contribution in profit sharing plan	$ 197	$ 194	$ 0
Amortization related to restricted stock awards	3,759	6,040	13,015
Restricted stock awards to directors	0	0	35,145
Fair value of restricted stock awards to directors	0	0	149
Amount capitalized in development activities	0	0	45
Unearned compensation related to unvested restricted stock awards	5,141
Weighted average period during which unrecognized compensation is expected to be incurred	0.79
Restricted stock granted to chief executive officer			1,000,000
Cash awards granted to management member	1,810	688	792
Number of service period over which service awards amortized			4 years
Restricted Unit Awards [Member]
Share Based Compensation (Textual) [Abstract]
Fair value at grant date of restricted stock	3,248	3,336	7,406
Vesting period of stock awards granted to employees, minimum	3 years
Vesting period of stock awards granted to employees, maximum	4 years
Stock awards granted to directors	5 years
Restricted stock and unit awards to employees	292,339	573,198	1,473,600
Service Awards [Member]
Share Based Compensation (Textual) [Abstract]
Number of installment of restricted stock units			4
Restricted stock and unit awards to employees			600,000
Performance Awards I [Member]
Share Based Compensation (Textual) [Abstract]
Number of installment of restricted stock units			4
Restricted stock and unit awards to employees			400,000
Restricted stock to be vest up to first installment			100,000
Restricted stock to be vest up to second installment			200,000
Restricted stock to be vest up to third installment			300,000
Restricted stock to be vest up to fourth installment			400,000
Performance Awards II [Member]
Share Based Compensation (Textual) [Abstract]
Fair value at grant date of restricted stock			1,392
Share Based Compensation Arrangement By Share Based Payment Award Shares Issued	39,100
Restricted stock unit granted to management members			473,600
Restricted Stock [Member] \| Chief Executive Officer [Member]
Share Based Compensation (Textual) [Abstract]
Fair value at grant date of restricted stock			$ 6,014
Service And Performance Awards One [Member]
Share Based Compensation (Textual) [Abstract]
Share Based Compensation Arrangement By Share Based Payment Award Shares Issued	525,000

The amount of a cash bonus paid or to be paid to certain members of management.

No definition available.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to a director who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of years over which the service requirement of the performance shares vest.

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No definition available.

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The number of grants made to Directors during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

No definition available.

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The number of grants made to the Chief Executive Officer during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

No definition available.

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The number of restricted units that will vest based on service requirements upon the 1-year anniversary of grant, subject to market condition vesting requirements.

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No definition available.

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The number of restricted units that will vest based on service requirements upon the 4-year anniversary of grant, subject to market condition vesting requirements.

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No definition available.

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The number of restricted units that will vest based on service requirements upon the 2-year anniversary of grant, subject to market condition vesting requirements.

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No definition available.

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The number of restricted units that will vest based on service requirements upon the 3-year anniversary of grant, subject to market condition vesting requirements.

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No definition available.

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A grant issuance of restricted units with service and performance conditions made to management during the period.

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The grant date fair value of an issuance of restricted units made to management and/or the Chief Executive Officer.

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No definition available.

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Share Based Compensation Arrangement By Share Based Payment Award Shares Issued

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The amount of the cost recognized during the period for defined contribution plans.

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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Description of the estimated period of time over which an employee is required to provide service in exchange for the equity-based payment award, which often is the vesting period. This period may be explicit or implicit based on the terms of the award, and may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

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Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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The maximum vesting term over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

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No definition available.

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The minimum vesting term over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

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No definition available.

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Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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