ACQUISITION, Fair Values of Consideration Transferred and Identifiable Net assets Acquired (Details) - USD ($) $ in Thousands		12 Months Ended
Oct. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Values of Consideration Transferred and Identifiable Net assets Acquired [Abstract]
Goodwill		$ 19,817	$ 20,177	$ 17,951
BCMZ [Member]
Fair Values of Consideration Transferred and Identifiable Net assets Acquired [Abstract]
Identifiable assets acquired	$ 2,986
Liabilities assumed	(1,688)
Net identifiable assets acquired	1,298	1,298	0
Goodwill	1,290	1,290	0
Net assets acquired	2,588	2,588	0
Fair value of consideration transferred	$ 2,588	$ 2,588	$ 0

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of assets acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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