FAIR VALUE DISCLOSURES - Valuation of financial instruments measured at fair value on a recurring basis (Details) (Fair value on a recurring basis, USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Quoted prices in active markets for identical assets (Level 1)
Assets:
Trading securities
Available for sale securities	330	380
Significant other observable inputs (Level 2)
Assets:
Trading securities	11,671	11,103
Available for sale securities
Significant unobservable inputs (Level 3)
Assets:
Trading securities
Available for sale securities