Taxes - Changes in the Reserve for Income Taxes, Excluding Interest and Penalties (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Balance of reserve for income taxes	$ 5,296	$ 5,127
Gross amounts of decreases in unrecognized tax benefits as a result of tax positions taken in prior periods		(56)
Unrecognized Tax Benefits, Period Increase (Decrease)	11
Gross amounts of increases in unrecognized tax benefits as a result of tax positions taken in the current period	1,235	1,291
Gross amounts of decreases in unrecognized tax benefits relating to settlements with taxing authorities	0	0
Gross amounts of decreases in unrecognized tax benefits as a result of the expiration of the applicable statutes of limitations	(823)	(1,066)
Balance of reserve for income taxes	$ 5,719	$ 5,296

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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

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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 (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in 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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