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Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2013 | Sep. 30, 2012 | Sep. 30, 2013 | Sep. 30, 2012
Consolidated Statements of Comprehensive Income [Abstract] |  |  |  |
Net income (loss) | $ 84,432 | $ (29,671) | $ 187,280 | $ 60,233
Net unrealized gain (loss) on derivative instruments qualifying as hedges: |  |  |  |
Net unrealized gain (loss) on derivative instruments arising during the period, net of tax of $0 and $(5,377) for the three months ended and $(3,116) and $4,570 for the nine months ended in 2013 and 2012, respectively | 0 | (9,125) | (5,594) | 7,962
Reclassification adjustment for gain on derivative instruments included in net income, net of tax of $(297) and $(4,570) for the three months ended and $(2,246) and $(4,126) for the nine months ended in 2013 and 2012, respectively | (510) | (7,782) | (3,678) | (7,029)
Net unrealized gain (loss) on derivative instruments qualifying as hedges | (510) | (16,907) | (9,272) | 933
Net unrealized gain (loss) on available-for-sale investments: |  |  |  |
Net unrealized gain (loss) on available-for-sale investments arising during the period, net of tax of $(5) and $4 for the three months ended and $(106) and $(22) for the nine months ended in 2013 and 2012, respectively | (10) | 7 | (197) | (41)
Reclassification adjustment for loss on available-for-sale investments included in net income, net of tax of $20 and $17 for the three months ended and $63 and $54 for the nine months ended in 2013 and 2012, respectively | 38 | 32 | 117 | 101
Net unrealized gain (loss) on available-for-sale investments | 28 | 39 | (80) | 60
Amortization of postretirement liability losses included in net periodic benefit cost, net of tax of $166 and $1,027 for the three and nine months ended in 2013 | 271 | 0 | 1,344 | 0
Foreign currency translation adjustment recognized during the period, net of tax of $(12) and $(10) for the three months ended and $(209) and $(275) for the nine months ended in 2013 and 2012, respectively | (20) | (8) | (351) | (443)
Reclassification adjustment for loss on foreign currency translation adjustment included in net income, net of tax of $70 and $2 for the three months ended and $70 and $2 for the nine months ended in 2013 and 2012, respectively | 115 | 3 | 143 | 3
Foreign currency translation adjustment | 95 | (5) | (208) | (440)
Other comprehensive income (loss) | (116) | (16,873) | (8,216) | 553
Comprehensive income (loss) | 84,316 | (46,544) | 179,064 | 60,786
Comprehensive loss attributable to noncontrolling interest | (24) | 0 | (204) | 0
Comprehensive income (loss) attributable to common stockholders | $ 84,340 | $ (46,544) | $ 179,268 | $ 60,786

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