INVESTMENTS (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairments, available-for-sale securities	$ 0	$ 16,000
Single largest loss position	68,000	145,000
Second largest loss position	58,000	99,000
Third largest loss position	$ 56,000	$ 94,000
Maximum
Gain (Loss) on Investments [Line Items]
Percent of investment portfolio below investment grade	4.00%

The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=82896770&loc=SL6284422-111562

Name:	us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration