Income Taxes - Earnings Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings before income taxes
Earnings before income taxes	$ 58,103	$ 40,253	$ 57,245
U.S.
Earnings before income taxes
Earnings before income taxes	30,815	9,315	25,746
Non-U.S.
Earnings before income taxes
Earnings before income taxes	$ 27,288	$ 30,938	$ 31,499

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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