Summarized Financial Information of Unconsolidated Joint Ventures (Assets, Liabilities, and Equity) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Current assets	$ 40,934	$ 33,951
Noncurrent assets	4,947	5,545
Current liabilities	9,519	7,485
Shareholders’ equity	$ 36,362	$ 32,011

Amount of equity, including noncontrolling interest, reported by an equity method investment of the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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