v3.19.1

CONCENTRATION OF CREDIT RISK (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) markets	Dec. 31, 2017	Dec. 31, 2016
Concentration Risk [Line Items]
FDIC insured amount | $	$ 250,000
Number of primary markets (in markets) | markets	3
Sales Revenue, Net [Member] | Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%	0.00%
UNITED STATES | Sales Revenue, Net [Member] | Customers located in the United States
Concentration Risk [Line Items]
Concentration risk, percentage	95.00%	88.00%	97.00%

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- Definition

Represents the number of primary markets for the sale of the entity's products.

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The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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