Income Taxes (Details 3) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Balance, beginning of year	$ 9,985	$ 15,155
Increase based on tax positions related to prior years	5,725	17,099
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	(767)	(1,901)
Reductions related to settlements	(3,795)	(19,833)
Reductions for tax positions as a result of a lapse of the applicable statute of limitations	(939)	$ (535)
Balance, end of year	$ 10,209

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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Amount of decrease 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
-Topic 740
-SubTopic 10
-Section 50
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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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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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