XML 21 R29.htm IDEA: XBRL DOCUMENT v2.4.0.6
Financial Instruments (Details 1) (USD $)
In Thousands, unless otherwise specified
6 Months Ended
Jun. 30, 2012
Jun. 30, 2011
Changes in fair value of assets (liabilities) that are measured on a recurring basis using significant unobservable inputs (Level 3)    
Fair value at beginning of period $ (600) $ (10,000)
Realized and unrealized gains included in earnings 262 347
Settlements 38 53
Fair value at end of period $ (300) $ (9,600)