Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Unrecognized beginning balance	$ 3,680	$ 3,688
Additions based on tax positions related to the current year	245	329
Additions for tax positions of prior years	24	67
Reductions for tax positions of prior years	(240)	(204)
Reductions as a result of a lapse of applicable statute of limitations	(80)	(70)
Reductions due to settlements	(6)	(28)
Reductions due to settlements	74	102
Ending balance	$ 3,549	$ 3,680

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- Definition

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
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&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

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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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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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

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