POSTRETIREMENT MEDICAL BENEFITS AND PENSION - Pension Benefit Disclosures (Details) (Pension, USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 500,000	$ 534,000
Interest cost	1,747,000	1,625,000
Expected return on plan assets	(2,154,000)	(2,060,000)
Amortization of deferred items	359,000	741,000
Total net periodic benefit cost	452,000	840,000
Cash contributions during the period	600,000
Expected contributions during the remainder of 2014	$ 3,700,000