Intangible Assets (Details 1) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Assets [Member]
Annual amortization of intangible assets and liabilities
2012	$ 8,083
2013	12,358
2014	9,549
2015	7,159
2016	4,526
Thereafter	16,252
Total	57,927
Liabilities [Member]
Annual amortization of intangible assets and liabilities
2012	3,321
2013	6,308
2014	4,741
2015	2,597
2016	1,704
Thereafter	12,855
Total	$ 31,526

The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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- Definition

The amount of amortization expense expected to be recognized for the remainder of the finite-lived intangible asset useful life after the fifth succeeding fiscal year.

+ References

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The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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- Definition

The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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