4. INVESTMENTS IN MARKETABLE SECURITIES (Detail) (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Investments, Debt and Equity Securities [Abstract]
Trading Securities, Realized Gain (Loss)	$ (3,000)	$ 49,000
Trading Securities, Realized Loss	23,000	16,000
Trading Securities, Realized Gain	$ 20,000	$ 65,000

This item represents the gain (loss) realized during the period from the sale of trading securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph c

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration