Income Taxes Reconciliation of the change in unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of the change in unrecognized tax benefits [Roll Forward]
Unrecognized Tax Benefits, beginning of period	$ 38,992	$ 32,911	$ 173,310
Increases related to tax positions taken during a prior period	224	5,763	0
Decreases related to tax positions taken during a prior period	(13,218)	0	(133,883)
Increases related to tax positions taken during the current period	114	318	237
Decreases related to settlements with taxing authorities	(707)	0	(6,753)
Reductions as a result of a lapse of the statute of limitations	(3,903)	0	0
Unrecognized Tax Benefits, end of period	$ 21,502	$ 38,992	$ 32,911

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
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

Reference 2: 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

+ Details

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

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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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.

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

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

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