Income Taxes and Distributions (Details 5) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Activities related to unrecognized tax benefits
Gross unrecognized tax benefits at beginning of year	$ 6,098,000	$ 6,098,000
Increases (decreases) in unrecognized tax benefits related to a prior year	76,000	(248,000)
Increases (decreases) in unrecognized tax benefits related to the current year	260,000	394,000
Lapse in statute of limitations for assessment	(21,000)	(146,000)
Gross unrecognized tax benefits at end of year	$ 6,413,000	$ 6,098,000

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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

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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

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-Name Accounting Standards Codification

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

+ References

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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

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