Income Taxes and Distributions (Details 5) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Activities related to unrecognized tax benefits
Gross unrecognized tax benefits at beginning of year	$ 6,413,000us-gaap_UnrecognizedTaxBenefits	$ 6,098,000us-gaap_UnrecognizedTaxBenefits
Increases (decreases) in unrecognized tax benefits related to a prior year	0	76,000
Increases (decreases) in unrecognized tax benefits related to the current year	0	260,000
Lapse in statute of limitations for assessment	(5,556,000)	(21,000)
Gross unrecognized tax benefits at end of year	$ 857,000us-gaap_UnrecognizedTaxBenefits	$ 6,413,000us-gaap_UnrecognizedTaxBenefits

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Paragraph 15A

-Subparagraph (a)

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 15A

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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