DERIVATIVE INSTRUMENTS (Details) (USD $) In Thousands, unless otherwise specified																								9 Months Ended
	Sep. 30, 2012 Swaps Natural Gas (NYMEX HH) Term October 2012 to December 2012		Sep. 30, 2012 Swaps Natural Gas (NYMEX HH) Term October 2012 to December 2012 Natural Gas Written Put and Call Spread	Sep. 30, 2012 Swaps Natural Gas (NYMEX HH) Term October 2012 to December 2012 Minimum Natural Gas Written Put and Call Spread	Sep. 30, 2012 Swaps Natural Gas (NYMEX HH) Term October 2012 to December 2012 Maximum Natural Gas Written Put and Call Spread	Sep. 30, 2012 Swaps Natural Gas (NYMEX HH) Term October 2012 to December 2012 NYMEX HH Price Below 3.53 Natural Gas Written Put and Call Spread	Sep. 30, 2012 Swaps Natural Gas (NYMEX HH) Term October 2012 to December 2012 NYMEX HH Price Range Between 4.00 and 4.50 Natural Gas Written Put and Call Spread	Sep. 30, 2012 Swaps Natural Gas (NYMEX HH) Term October 2012 to December 2012 NYMEX HH Price 4.50 or Above Natural Gas Written Put and Call Spread	Sep. 30, 2012 Swaps Natural Gas (NYMEX HH) Term Calendar 2013	Oct. 24, 2012 Swaps Natural Gas (NYMEX HH) Term Calendar 2014 Subsequent Event		Sep. 30, 2012 Swaps Oil (NYMEX WTI) Term October 2012 to December 2012	Sep. 30, 2012 Swaps Oil (NYMEX WTI) Term Calendar 2013	Sep. 30, 2012 Swaps NGLs (OPIS Refined Products) Term October 2012 to December 2012	Sep. 30, 2012 Swaptions Natural Gas (NYMEX HH) Term Calendar 2013 Expires December 2012 Weighted Average Hedged Price 4.02	Sep. 30, 2012 Swaptions Natural Gas (NYMEX HH) Term Calendar 2013 Expires December 2012 Weighted Average Hedged Price 4.01	Oct. 24, 2012 Swaptions Natural Gas (NYMEX HH) Term Calendar 2014 Expires December 2013 Subsequent Event		Sep. 30, 2012 Swaptions Oil (NYMEX WTI) Term Calendar 2013 Expires December 2012 Weighted Average Hedged Price 95.00	Sep. 30, 2012 Swaptions Oil (NYMEX WTI) Term Calendar 2014 Expires December 2013 Weighted Average Hedged Price 110.00	Sep. 30, 2012 Swaptions Oil (NYMEX WTI) Term Calendar 2014 Expires December 2013 Weighted Average Hedged Price 109.00	Sep. 30, 2012 Swaptions Oil (NYMEX WTI) Term Calendar 2014 Expires December 2013 Weighted Average Hedged Price 100.00	Sep. 30, 2012 Swaptions Oil (NYMEX WTI) Term Calendar 2015 Expires December 2014 Weighted Average Hedged Price 100.00	Sep. 30, 2012 Interest Rate Swaps Remaining Term October 2012 To February 2014	Sep. 30, 2012 Put Option Oil (NYMEX WTI) Term Monthly October 2012 To December 2012 Expires monthly October 2012 to December 2012
Commodity Derivatives
Notional amount (Bbtu/Barrels per day)	155	[1]	50						160	40	[2]	4,500	4,000	2,000	30	10	40	[2]	2,000	2,000	1,000	2,000	3,000		5,000
Weighted Average Hedged Price per MMBtu	4.63	[1]	5.30					5.80	3.98	4.50	[2]				4.02	4.01	4.50	[2]
Weighted Average Hedged Price per Bbl												97.26	95.53	45.22					95.00	110.00	109.00	100.00	100.00		75.00
Derivative Price Per Unit Call Spread						1.77
Derivative, Price Risk Call Option Strike Price				4.00	4.50
Derivative Price Risk Put Option Strike Price			3.53
Derivative, Price Added to Call Spread							5.30
Interest Rate Derivatives
Notional Amount																								$ 500,000
Reference rate for Interest Rate Swaps Weighted Average Floating Rate																								1 month LIBOR
Weighted Average Floating Rate added to reference rate (as a percent)																								5.89%
Weighted Average Fixed Rate (as a percent)																								8.50%

[1] 50 Bbtu per day of 2012 gas swaps with a weighted average hedged price per MMBtu of $5.30 are layered with a written put of $3.53 and a call spread of $4.00 to $4.50. Together with the put and call spread, Forest will receive the $5.30 swap price on 50 Bbtu per day except as follows: Forest will receive (i) NYMEX HH plus $1.77 when NYMEX HH is below $3.53; (ii) $5.30 plus the value of the call spread when NYMEX HH is between $4.00 and $4.50; and (iii) $5.80 when NYMEX HH is $4.50 or above.

[2] In connection with entering into these natural gas swaps with premium hedged prices, Forest granted options to the counterparties to enter into gas swaps with Forest for Calendar 2014 covering 40 Bbtu per day at a weighted average hedged price per MMBtu of $4.50, with such options expiring in December 2013.