Accrued Liabilities (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Contract liabilities	$ 9,025
Other accruals	20,581	$ 16,557
Cumulative effect of adopting ASC 606 [Member]
Increased Contract loss	14,900
Contract liabilities	700
Other accruals	$ 1,600

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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