Long-Term Incentive Plan (Details Textuals) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
Long-Term Incentive Plan (Textuals) [Abstract]
Minimum percentage of performance-based restricted stock units and performance-based cash awards that can be earned	0.00%	0.00%
Maximum percentage of performance-based restricted stock units and performance-based cash awards that can be earned	200.00%	200.00%
Compensation expense recognized for performance-based restricted stock units and performance-based cash awards	$ 808	$ 1,278
Performance-based Restricted Stock Units [Member]
Long-Term Incentive Plan (Textuals) [Abstract]
Granted at target level, Shares		78,131
Minimum number of performance-based restricted stock units that can be earned	0	0
Maximum number of performance-based restricted stock units that can be earned	156,262	156,262
Performance-based Cash Awards [Member]
Long-Term Incentive Plan (Textuals) [Abstract]
Granted at target level, Value		4,599
Minimum amount of performance-based cash awards that can be earned	0	0
Maximum amount of performance-based cash awards that can be earned	$ 9,198	$ 9,198

Represents the expense recognized during the period arising from performance-based equity and cash compensation arrangements with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Long term incentive plan.

+ Details

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- Definition

The maximum number of performance-based restricted stock units that participants can earn for performance-based target awards under the Company's long-term incentive plan.

+ Details

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- Definition

The maximum percentage of granted target awards that participants can earn for performance-based awards under the Company's long-term incentive plan.

+ Details

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- Definition

The minimum number of performance-based restricted stock units that participants can earn for performance-based target awards under the Company's long-term incentive plan.

+ Details

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- Definition

The minimum percentage of granted target awards that participants can earn for performance-based awards under the Company's long-term incentive plan.

+ Details

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- Definition

The target value of performance-based cash awards made during the period.

+ Details

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- Definition

The maximum amount of a performance-based target cash award that can be earned during the performance period.

+ Details

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- Definition

The minimum amount of a performance-based target cash award that can be earned during the performance period.

+ Details

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(c)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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