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Consolidating Financial Statements (Tables) | 12 Months Ended
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Dec. 31, 2012
Schedule of Consolidating Balance Sheet | Consolidating Balance Sheet (In thousands, except share data)
|  | December 31, 2012 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
ASSETS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 133,797 |  |  | $ | 79,650 |  |  | $ | — |  |  | $ | 213,447 |
Short-term investments |  |  | 25,891 |  |  |  | — |  |  |  | — |  |  |  | 25,891 |
Accounts receivable – oil and gas revenues |  |  | — |  |  |  | 110,341 |  |  |  | — |  |  |  | 110,341 |
Accounts receivable – joint interest partners |  |  | — |  |  |  | 99,194 |  |  |  | — |  |  |  | 99,194 |
Accounts receivable – affiliates |  |  | 310 |  |  |  | 5,845 |  |  |  | (6,155 | ) |  |  |  |
Inventory |  |  | — |  |  |  | 20,707 |  |  |  | — |  |  |  | 20,707 |
Prepaid expenses |  |  | 313 |  |  |  | 1,457 |  |  |  | — |  |  |  | 1,770 |
Advances to joint interest partners |  |  | — |  |  |  | 1,985 |  |  |  | — |  |  |  | 1,985 |
Derivative instruments |  |  | — |  |  |  | 19,016 |  |  |  | — |  |  |  | 19,016 |
Other current assets |  |  | 235 |  |  |  | 100 |  |  |  | — |  |  |  | 335 |
Total current assets |  |  | 160,546 |  |  |  | 338,295 |  |  |  | (6,155 | ) |  |  | 492,686 |
Property, plant and equipment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Oil and gas properties (successful efforts method) |  |  | — |  |  |  | 2,348,128 |  |  |  | — |  |  |  | 2,348,128 |
Other property and equipment |  |  | — |  |  |  | 49,732 |  |  |  | — |  |  |  | 49,732 |
Less: accumulated depreciation, depletion, amortization and impairment |  |  | — |  |  |  | (391,260 | ) |  |  | — |  |  |  | (391,260 | )
Total property, plant and equipment, net |  |  | — |  |  |  | 2,006,600 |  |  |  | — |  |  |  | 2,006,600 |
Investments in and advances to subsidiaries |  |  | 1,807,010 |  |  |  | — |  |  |  | (1,807,010 | ) |  |  | — |
Derivative instruments |  |  | — |  |  |  | 4,981 |  |  |  | — |  |  |  | 4,981 |
Deferred income taxes |  |  | 42,746 |  |  |  | — |  |  |  | (42,746 | ) |  |  | — |
Deferred costs and other assets |  |  | 20,748 |  |  |  | 3,779 |  |  |  | — |  |  |  | 24,527 |
Total assets |  | $ | 2,031,050 |  |  | $ | 2,353,655 |  |  | $ | (1,855,911 | ) |  | $ | 2,528,794 |
LIABILITIES AND STOCKHOLDERS’ EQUITY |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accounts payable |  | $ | 9 |  |  | $ | 12,482 |  |  | $ | — |  |  | $ | 12,491 |
Accounts payable – affiliates |  |  | 5,845 |  |  |  | 310 |  |  |  | (6,155 | ) |  |  |  |
Advances from joint interest partners |  |  | — |  |  |  | 21,176 |  |  |  | — |  |  |  | 21,176 |
Revenues and production taxes payable |  |  | — |  |  |  | 71,553 |  |  |  | — |  |  |  | 71,553 |
Accrued liabilities |  |  | 100 |  |  |  | 189,763 |  |  |  | — |  |  |  | 189,863 |
Accrued interest payable |  |  | 30,091 |  |  |  | 5 |  |  |  | — |  |  |  | 30,096 |
Derivative instruments |  |  | — |  |  |  | 1,048 |  |  |  | — |  |  |  | 1,048 |
Deferred income taxes |  |  | — |  |  |  | 4,558 |  |  |  | — |  |  |  | 4,558 |
Total current liabilities |  |  | 36,045 |  |  |  | 300,895 |  |  |  | (6,155 | ) |  |  | 330,785 |
Long-term debt |  |  | 1,200,000 |  |  |  | — |  |  |  | — |  |  |  | 1,200,000 |
Asset retirement obligations |  |  | — |  |  |  | 22,956 |  |  |  | — |  |  |  | 22,956 |
Derivative instruments |  |  | — |  |  |  | 380 |  |  |  | — |  |  |  | 380 |
Deferred income taxes |  |  | — |  |  |  | 220,417 |  |  |  | (42,746 | ) |  |  | 177,671 |
Other liabilities |  |  | — |  |  |  | 1,997 |  |  |  | — |  |  |  | 1,997 |
Total liabilities |  |  | 1,236,045 |  |  |  | 546,645 |  |  |  | (48,901 | ) |  |  | 1,733,789 |
Stockholders’ equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital contributions from affiliates |  |  | — |  |  |  | 1,586,780 |  |  |  | (1,586,780 | ) |  |  | — |
Common stock, $0.01 par value; 300,000,000 shares authorized; 93,432,712 issued and 93,303,298 outstanding |  |  | 925 |  |  |  | — |  |  |  | — |  |  |  | 925 |
Treasury stock, at cost; 129,414 shares |  |  | (3,796 | ) |  |  | — |  |  |  | — |  |  |  | (3,796 | )
Additional paid-in-capital |  |  | 657,943 |  |  |  | 8,743 |  |  |  | (8,743 | ) |  |  | 657,943 |
Retained earnings |  |  | 139,933 |  |  |  | 211,487 |  |  |  | (211,487 | ) |  |  | 139,933 |
Total stockholders’ equity |  |  | 795,005 |  |  |  | 1,807,010 |  |  |  | (1,807,010 | ) |  |  | 795,005 |
Total liabilities and stockholders’ equity |  | $ | 2,031,050 |  |  | $ | 2,353,655 |  |  | $ | (1,855,911 | ) |  | $ | 2,528,794 |
Consolidating Balance Sheet (In thousands, except share data)
|  | December 31, 2011 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
ASSETS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 443,482 |  |  | $ | 27,390 |  |  | $ | — |  |  | $ | 470,872 |
Short-term investments |  |  | 19,994 |  |  |  | — |  |  |  | — |  |  |  | 19,994 |
Accounts receivable – oil and gas revenues |  |  | — |  |  |  | 52,164 |  |  |  | — |  |  |  | 52,164 |
Accounts receivable – joint interest partners |  |  | — |  |  |  | 67,268 |  |  |  | — |  |  |  | 67,268 |
Accounts receivable – affiliates |  |  | 88 |  |  |  | 1,540 |  |  |  | (1,628 | ) |  |  | — |
Inventory |  |  | — |  |  |  | 3,543 |  |  |  | — |  |  |  | 3,543 |
Prepaid expenses |  |  | 309 |  |  |  | 1,831 |  |  |  | — |  |  |  | 2,140 |
Advances to joint interest partners |  |  | — |  |  |  | 3,935 |  |  |  | — |  |  |  | 3,935 |
Deferred income taxes |  |  | — |  |  |  | 3,233 |  |  |  | — |  |  |  | 3,233 |
Other current assets |  |  | 18 |  |  |  | 473 |  |  |  | — |  |  |  | 491 |
Total current assets |  |  | 463,891 |  |  |  | 161,377 |  |  |  | (1,628 | ) |  |  | 623,640 |
Property, plant and equipment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Oil and gas properties (successful efforts method) |  |  | — |  |  |  | 1,235,357 |  |  |  | — |  |  |  | 1,235,357 |
Other property and equipment |  |  | — |  |  |  | 20,859 |  |  |  | — |  |  |  | 20,859 |
Less: accumulated depreciation, depletion, amortization and impairment |  |  | — |  |  |  | (176,261 | ) |  |  | — |  |  |  | (176,261 | )
Total property, plant and equipment, net |  |  | — |  |  |  | 1,079,955 |  |  |  | — |  |  |  | 1,079,955 |
Investments in and advances to subsidiaries |  |  | 958,880 |  |  |  | — |  |  |  | (958,880 | ) |  |  | — |
Derivative instruments |  |  | — |  |  |  | 4,362 |  |  |  | — |  |  |  | 4,362 |
Deferred income taxes |  |  | 13,158 |  |  |  | — |  |  |  | (13,158 | ) |  |  | — |
Deferred costs and other assets |  |  | 15,742 |  |  |  | 3,683 |  |  |  | — |  |  |  | 19,425 |
Total assets |  | $ | 1,451,671 |  |  | $ | 1,249,377 |  |  | $ | (973,666 | ) |  | $ | 1,727,382 |
LIABILITIES AND STOCKHOLDERS’ EQUITY |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accounts payable |  | $ | 23 |  |  | $ | 12,184 |  |  | $ | — |  |  | $ | 12,207 |
Accounts payable - affiliates |  |  | 1,540 |  |  |  | 88 |  |  |  | (1,628 | ) |  |  | — |
Advances from joint interest partners |  |  | — |  |  |  | 9,064 |  |  |  | — |  |  |  | 9,064 |
Revenues and production taxes payable |  |  | — |  |  |  | 19,468 |  |  |  | — |  |  |  | 19,468 |
Accrued liabilities |  |  | 103 |  |  |  | 119,589 |  |  |  | — |  |  |  | 119,692 |
Accrued interest payable |  |  | 15,767 |  |  |  | 7 |  |  |  | — |  |  |  | 15,774 |
Derivative instruments |  |  | — |  |  |  | 5,907 |  |  |  | — |  |  |  | 5,907 |
Other current liabilities |  |  | — |  |  |  | 472 |  |  |  | — |  |  |  | 472 |
Total current liabilities |  |  | 17,433 |  |  |  | 166,779 |  |  |  | (1,628 | ) |  |  | 182,584 |
Long-term debt |  |  | 800,000 |  |  |  | — |  |  |  | — |  |  |  | 800,000 |
Asset retirement obligations |  |  | — |  |  |  | 13,075 |  |  |  | — |  |  |  | 13,075 |
Derivative instruments |  |  | — |  |  |  | 3,505 |  |  |  | — |  |  |  | 3,505 |
Deferred income taxes |  |  | — |  |  |  | 106,141 |  |  |  | (13,158 | ) |  |  | 92,983 |
Other liabilities |  |  | — |  |  |  | 997 |  |  |  | — |  |  |  | 997 |
Total liabilities |  |  | 817,433 |  |  |  | 290,497 |  |  |  | (14,786 | ) |  |  | 1,093,144 |
Stockholders’ equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital contributions from affiliates |  |  | — |  |  |  | 941,575 |  |  |  | (941,575 | ) |  |  | — |
Common stock, $0.01 par value; 300,000,000 shares authorized; 92,483,393 issued and 92,460,914 outstanding |  |  | 921 |  |  |  | — |  |  |  | — |  |  |  | 921 |
Treasury stock, at cost; 22,479 shares |  |  | (602 | ) |  |  | — |  |  |  | — |  |  |  | (602 | )
Additional paid-in-capital |  |  | 647,374 |  |  |  | 8,743 |  |  |  | (8,743 | ) |  |  | 647,374 |
Retained earnings (deficit) |  |  | (13,455 | ) |  |  | 8,562 |  |  |  | (8,562 | ) |  |  | (13,455 | )
Total stockholders’ equity |  |  | 634,238 |  |  |  | 958,880 |  |  |  | (958,880 | ) |  |  | 634,238 |
Total liabilities and stockholders’ equity |  | $ | 1,451,671 |  |  | $ | 1,249,377 |  |  | $ | (973,666 | ) |  | $ | 1,727,382 |
Schedule of Consolidating Statement of Operations | Consolidating Statement of Operations (In thousands)
|  | Years Ended December 31, 2012 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Revenues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Oil and gas revenues |  | $ | — |  |  | $ | 670,491 |  |  | $ | — |  |  | $ | 670,491 |
Well services revenues |  |  | — |  |  |  | 16,177 |  |  |  | — |  |  |  | 16,177 |
Total revenues |  |  | — |  |  |  | 686,668 |  |  |  | — |  |  |  | 686,668 |
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease operating expenses |  |  | — |  |  |  | 54,924 |  |  |  | — |  |  |  | 54,924 |
Well services operating expense |  |  | — |  |  |  | 11,774 |  |  |  | — |  |  |  | 11,774 |
Marketing, transportation and gathering expenses |  |  | — |  |  |  | 9,257 |  |  |  | — |  |  |  | 9,257 |
Production taxes |  |  | — |  |  |  | 62,965 |  |  |  | — |  |  |  | 62,965 |
Depreciation, depletion and amortization |  |  | — |  |  |  | 206,734 |  |  |  | — |  |  |  | 206,734 |
Exploration expenses |  |  | — |  |  |  | 3,250 |  |  |  | — |  |  |  | 3,250 |
Impairment of oil and gas properties |  |  | — |  |  |  | 3,581 |  |  |  | — |  |  |  | 3,581 |
Loss on sale of properties |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
General and administrative expenses |  |  | 12,591 |  |  |  | 44,599 |  |  |  | — |  |  |  | 57,190 |
Total expenses |  |  | 12,591 |  |  |  | 397,084 |  |  |  | — |  |  |  | 409,675 |
Operating income (loss) |  |  | (12,591 | ) |  |  | 289,584 |  |  |  | — |  |  |  | 276,993 |
Other income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  | 202,924 |  |  |  | — |  |  |  | (202,924 | ) |  |  | — |
Net gain on derivative instruments |  |  | — |  |  |  | 34,164 |  |  |  | — |  |  |  | 34,164 |
Interest expense |  |  | (67,651 | ) |  |  | (2,492 | ) |  |  | — |  |  |  | (70,143 | )
Other income (expense) |  |  | 1,118 |  |  |  | 3,742 |  |  |  | — |  |  |  | 4,860 |
Total other income (expense) |  |  | 136,391 |  |  |  | 35,414 |  |  |  | (202,924 | ) |  |  | (31,119 | )
Income before income taxes |  |  | 123,800 |  |  |  | 324,998 |  |  |  | (202,924 | ) |  |  | 245,874 |
Income tax benefit (expense) |  |  | 29,588 |  |  |  | (122,074 | ) |  |  | — |  |  |  | (92,486 | )
Net income |  | $ | 153,388 |  |  | $ | 202,924 |  |  | $ | (202,924 | ) |  | $ | 153,388 |
Consolidating Statement of Operations (In thousands)
|  | Years Ended December 31, 2011 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Oil and gas revenues |  | $ | — |  |  | $ | 330,422 |  |  | $ | — |  |  | $ | 330,422 |
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease operating expenses |  |  | — |  |  |  | 32,707 |  |  |  | — |  |  |  | 32,707 |
Marketing, transportation and gathering expenses |  |  | — |  |  |  | 1,365 |  |  |  | — |  |  |  | 1,365 |
Production taxes |  |  | — |  |  |  | 33,865 |  |  |  | — |  |  |  | 33,865 |
Depreciation, depletion and amortization |  |  | — |  |  |  | 74,981 |  |  |  | — |  |  |  | 74,981 |
Exploration expenses |  |  | — |  |  |  | 1,685 |  |  |  | — |  |  |  | 1,685 |
Impairment of oil and gas properties |  |  | — |  |  |  | 3,610 |  |  |  | — |  |  |  | 3,610 |
Loss on sale of properties |  |  | — |  |  |  | 207 |  |  |  | — |  |  |  | 207 |
General and administrative expenses |  |  | 5,505 |  |  |  | 23,930 |  |  |  | — |  |  |  | 29,435 |
Total expenses |  |  | 5,505 |  |  |  | 172,350 |  |  |  | — |  |  |  | 177,855 |
Operating income (loss) |  |  | (5,505 | ) |  |  | 158,072 |  |  |  | — |  |  |  | 152,567 |
Other income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  | 99,836 |  |  |  | — |  |  |  | (99,836 | ) |  |  | — |
Net gain on derivative instruments |  |  | — |  |  |  | 1,595 |  |  |  | — |  |  |  | 1,595 |
Interest expense |  |  | (28,310 | ) |  |  | (1,308 | ) |  |  | — |  |  |  | (29,618 | )
Other income (expense) |  |  | 1,165 |  |  |  | 470 |  |  |  | — |  |  |  | 1,635 |
Total other income (expense) |  |  | 72,691 |  |  |  | 757 |  |  |  | (99,836 | ) |  |  | (26,388 | )
Income before income taxes |  |  | 67,186 |  |  |  | 158,829 |  |  |  | (99,836 | ) |  |  | 126,179 |
Income tax benefit (expense) |  |  | 12,204 |  |  |  | (58,993 | ) |  |  | — |  |  |  | (46,789 | )
Net income |  | $ | 79,390 |  |  | $ | 99,836 |  |  | $ | (99,836 | ) |  | $ | 79,390 |
Consolidating Statement of Operations (In thousands)
|  | Year Ended December 31, 2010 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Oil and gas revenues |  | $ | — |  |  | $ | 128,927 |  |  | $ | — |  |  | $ | 128,927 |
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease operating expenses |  |  | — |  |  |  | 14,118 |  |  |  | — |  |  |  | 14,118 |
Marketing, transportation and gathering expenses |  |  | — |  |  |  | 464 |  |  |  | — |  |  |  | 464 |
Production taxes |  |  | — |  |  |  | 13,768 |  |  |  | — |  |  |  | 13,768 |
Depreciation, depletion and amortization |  |  | — |  |  |  | 37,832 |  |  |  | — |  |  |  | 37,832 |
Exploration expenses |  |  | — |  |  |  | 297 |  |  |  | — |  |  |  | 297 |
Impairment of oil and gas properties |  |  | — |  |  |  | 11,967 |  |  |  | — |  |  |  | 11,967 |
Stock-based compensation expenses |  |  | — |  |  |  | 8,743 |  |  |  | — |  |  |  | 8,743 |
General and administrative expenses |  |  | 2,780 |  |  |  | 16,965 |  |  |  | — |  |  |  | 19,745 |
Total expenses |  |  | 2,780 |  |  |  | 104,154 |  |  |  | — |  |  |  | 106,934 |
Operating income (loss) |  |  | (2,780 | ) |  |  | 24,773 |  |  |  | — |  |  |  | 21,993 |
Other income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  | (28,124 | ) |  |  | — |  |  |  | 28,124 |  |  |  | — |
Net loss on derivative instruments |  |  | — |  |  |  | (7,653 | ) |  |  | — |  |  |  | (7,653 | )
Interest expense |  |  | — |  |  |  | (1,357 | ) |  |  | — |  |  |  | (1,357 | )
Other income (expense) |  |  | 255 |  |  |  | 29 |  |  |  | — |  |  |  | 284 |
Total other income (expense) |  |  | (27,869 | ) |  |  | (8,981 | ) |  |  | 28,124 |  |  |  | (8,726 | )
Income (loss) before income taxes |  |  | (30,649 | ) |  |  | 15,792 |  |  |  | 28,124 |  |  |  | 13,267 |
Income tax benefit (expense) |  |  | 954 |  |  |  | (43,916 | ) |  |  | — |  |  |  | (42,962 | )
Net loss |  | $ | (29,695 | ) |  | $ | (28,124 | ) |  | $ | 28,124 |  |  | $ | (29,695 | )
Schedule of Consolidating Statement of Cash Flows | Consolidating Statement of Cash Flows (In thousands)
|  | Year Ended December 31, 2012 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Cash flows from operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income |  | $ | 153,388 |  |  | $ | 202,924 |  |  | $ | (202,924 | ) |  | $ | 153,388 |
Adjustments to reconcile net income to net cash provided by (used in) operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  | (202,924 | ) |  |  | — |  |  |  | 202,924 |  |  |  | — |
Depreciation, depletion and amortization |  |  | — |  |  |  | 206,734 |  |  |  | — |  |  |  | 206,734 |
Impairment of oil and gas properties |  |  | — |  |  |  | 3,581 |  |  |  | — |  |  |  | 3,581 |
Deferred income taxes |  |  | (29,588 | ) |  |  | 122,067 |  |  |  | — |  |  |  | 92,479 |
Derivative instruments |  |  | — |  |  |  | (34,164 | ) |  |  | — |  |  |  | (34,164 | )
Stock-based compensation expenses |  |  | 10,219 |  |  |  | 114 |  |  |  | — |  |  |  | 10,333 |
Debt discount amortization and other |  |  | 2,277 |  |  |  | 533 |  |  |  | — |  |  |  | 2,810 |
Working capital and other changes: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in accounts receivable |  |  | (222 | ) |  |  | (94,106 | ) |  |  | 4,225 |  |  |  | (90,103 | )
Change in inventory |  |  | — |  |  |  | (29,313 | ) |  |  | — |  |  |  | (29,313 | )
Change in prepaid expenses |  |  | (4 | ) |  |  | 350 |  |  |  | — |  |  |  | 346 |
Change in other current assets |  |  | (217 | ) |  |  | 373 |  |  |  | — |  |  |  | 156 |
Change in other assets |  |  | 25 |  |  |  | (120 | ) |  |  | — |  |  |  | (95 | )
Change in accounts payable and accrued liabilities |  |  | 18,612 |  |  |  | 62,319 |  |  |  | (4,225 | ) |  |  | 76,706 |
Change in other current liabilities |  |  | — |  |  |  | (472 | ) |  |  | — |  |  |  | (472 | )
Net cash provided by (used in) operating activities |  |  | (48,434 | ) |  |  | 440,820 |  |  |  | — |  |  |  | 392,386 |
Cash flows from investing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital expenditures |  |  | — |  |  |  | (1,053,315 | ) |  |  | — |  |  |  | (1,053,315 | )
Derivative settlements |  |  | — |  |  |  | 6,545 |  |  |  | — |  |  |  | 6,545 |
Purchases of short-term investments |  |  | (126,213 | ) |  |  | — |  |  |  | — |  |  |  | (126,213 | )
Redemptions of short-term investments |  |  | 120,316 |  |  |  | — |  |  |  | — |  |  |  | 120,316 |
Advances to joint interest partners |  |  | — |  |  |  | 1,950 |  |  |  | — |  |  |  | 1,950 |
Advances from joint interest partners |  |  | — |  |  |  | 12,112 |  |  |  | — |  |  |  | 12,112 |
Net cash used in investing activities |  |  | (5,897 | ) |  |  | (1,032,708 | ) |  |  | — |  |  |  | (1,038,605 | )
Cash flows from financing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of senior notes |  |  | 400,000 |  |  |  | — |  |  |  | — |  |  |  | 400,000 |
Purchases of treasury stock |  |  | (3,194 | ) |  |  | — |  |  |  | — |  |  |  | (3,194 | )
Debt issuance costs |  |  | (7,307 | ) |  |  | (705 | ) |  |  | — |  |  |  | (8,012 | )
Investment in / capital contributions from subsidiaries |  |  | (644,853 | ) |  |  | 644,853 |  |  |  | — |  |  |  | — |
Net cash provided by (used in) financing activities |  |  | (255,354 | ) |  |  | 644,148 |  |  |  | — |  |  |  | 388,794 |
Increase (decrease) in cash and cash equivalents |  |  | (309,685 | ) |  |  | 52,260 |  |  |  | — |  |  |  | (257,425 | )
Cash and cash equivalents at beginning of period |  |  | 443,482 |  |  |  | 27,390 |  |  |  | — |  |  |  | 470,872 |
Cash and cash equivalents at end of period |  | $ | 133,797 |  |  | $ | 79,650 |  |  | $ | — |  |  | $ | 213,447 |
Consolidating Statement of Cash Flows (In thousands)
|  | Year Ended December 31, 2011 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Cash flows from operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income |  | $ | 79,390 |  |  | $ | 99,836 |  |  | $ | (99,836 | ) |  | $ | 79,390 |
Adjustments to reconcile net income to net cash provided by (used in) operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  | (99,836 | ) |  |  | — |  |  |  | 99,836 |  |  |  | — |
Depreciation, depletion and amortization |  |  | — |  |  |  | 74,981 |  |  |  | — |  |  |  | 74,981 |
Impairment of oil and gas properties |  |  | — |  |  |  | 3,610 |  |  |  | — |  |  |  | 3,610 |
Loss on sale of properties |  |  | — |  |  |  | 207 |  |  |  | — |  |  |  | 207 |
Deferred income taxes |  |  | (12,204 | ) |  |  | 58,993 |  |  |  | — |  |  |  | 46,789 |
Derivative instruments |  |  | — |  |  |  | (1,595 | ) |  |  | — |  |  |  | (1,595 | )
Stock-based compensation expenses |  |  | 3,656 |  |  |  | — |  |  |  | — |  |  |  | 3,656 |
Debt discount amortization and other |  |  | 1,196 |  |  |  | 365 |  |  |  | — |  |  |  | 1,561 |
Working capital and other changes: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in accounts receivable |  |  | (88 | ) |  |  | (66,134 | ) |  |  | 1,322 |  |  |  | (64,900 | )
Change in inventory |  |  | — |  |  |  | (2,550 | ) |  |  | — |  |  |  | (2,550 | )
Change in prepaid expenses |  |  | (73 | ) |  |  | (1,527 | ) |  |  | — |  |  |  | (1,600 | )
Change in other current assets |  |  | (18 | ) |  |  | (473 | ) |  |  | — |  |  |  | (491 | )
Change in other assets |  |  | (100 | ) |  |  | (39 | ) |  |  | — |  |  |  | (139 | )
Change in accounts payable and accrued liabilities |  |  | 17,127 |  |  |  | 20,511 |  |  |  | (1,322 | ) |  |  | 36,316 |
Change in other current liabilities |  |  | — |  |  |  | 472 |  |  |  | — |  |  |  | 472 |
Change in other liabilities |  |  | — |  |  |  | 317 |  |  |  | — |  |  |  | 317 |
Net cash provided by (used in) operating activities |  |  | (10,950 | ) |  |  | 186,974 |  |  |  | — |  |  |  | 176,024 |
Cash flows from investing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital expenditures |  |  | — |  |  |  | (613,223 | ) |  |  | — |  |  |  | (613,223 | )
Derivative settlements |  |  | — |  |  |  | (3,841 | ) |  |  | — |  |  |  | (3,841 | )
Purchases of short-term investments |  |  | (184,907 | ) |  |  | — |  |  |  | — |  |  |  | (184,907 | )
Redemptions of short-term investments |  |  | 164,913 |  |  |  | — |  |  |  | — |  |  |  | 164,913 |
Advances to joint interest partners |  |  | — |  |  |  | (497 | ) |  |  | — |  |  |  | (497 | )
Advances from joint interest partners |  |  | — |  |  |  | 5,963 |  |  |  | — |  |  |  | 5,963 |
Proceeds from equipment and property sales |  |  | — |  |  |  | 2,202 |  |  |  | — |  |  |  | 2,202 |
Net cash used in investing activities |  |  | (19,994 | ) |  |  | (609,396 | ) |  |  | — |  |  |  | (629,390 | )
Cash flows from financing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of senior notes |  |  | 800,000 |  |  |  | — |  |  |  | — |  |  |  | 800,000 |
Purchases of treasury stock |  |  | (602 | ) |  |  | — |  |  |  | — |  |  |  | (602 | )
Debt issuance costs |  |  | (16,838 | ) |  |  | (1,842 | ) |  |  | — |  |  |  | (18,680 | )
Investment in / capital contributions from subsidiaries |  |  | (428,074 | ) |  |  | 428,074 |  |  |  | — |  |  |  | — |
Net cash provided by financing activities |  |  | 354,486 |  |  |  | 426,232 |  |  |  | — |  |  |  | 780,718 |
Increase in cash and cash equivalents |  |  | 323,542 |  |  |  | 3,810 |  |  |  | — |  |  |  | 327,352 |
Cash and cash equivalents at beginning of period |  |  | 119,940 |  |  |  | 23,580 |  |  |  | — |  |  |  | 143,520 |
Cash and cash equivalents at end of period |  | $ | 443,482 |  |  | $ | 27,390 |  |  | $ | — |  |  | $ | 470,872 |
Consolidating Statement of Cash Flows (In thousands)
|  | Year Ended December 31, 2010 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Cash flows from operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | $ | (29,695 | ) |  | $ | (28,124 | ) |  | $ | 28,124 |  |  | $ | (29,695 | )
Adjustments to reconcile net loss to net cash provided by (used in) operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  | 28,124 |  |  |  | — |  |  |  | (28,124 | ) |  |  | — |
Depreciation, depletion and amortization |  |  | — |  |  |  | 37,832 |  |  |  | — |  |  |  | 37,832 |
Impairment of oil and gas properties |  |  | — |  |  |  | 11,967 |  |  |  | — |  |  |  | 11,967 |
Deferred income taxes |  |  | (954 | ) |  |  | 43,916 |  |  |  | — |  |  |  | 42,962 |
Derivative instruments |  |  | — |  |  |  | 7,653 |  |  |  | — |  |  |  | 7,653 |
Stock-based compensation expenses |  |  | 1,227 |  |  |  | 8,743 |  |  |  | — |  |  |  | 9,970 |
Debt discount amortization and other |  |  | — |  |  |  | 470 |  |  |  | — |  |  |  | 470 |
Working capital and other changes: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in accounts receivable |  |  | — |  |  |  | (44,756 | ) |  |  | 306 |  |  |  | (44,450 | )
Change in inventory |  |  | — |  |  |  | (498 | ) |  |  | — |  |  |  | (498 | )
Change in prepaid expenses |  |  | (236 | ) |  |  | (120 | ) |  |  | — |  |  |  | (356 | )
Change in other assets |  |  | — |  |  |  | (164 | ) |  |  | — |  |  |  | (164 | )
Change in accounts payable and accrued liabilities |  |  | 306 |  |  |  | 13,917 |  |  |  | (306 | ) |  |  | 13,917 |
Change in other liabilities |  |  | — |  |  |  | 4 |  |  |  | — |  |  |  | 4 |
Net cash provided by (used in) operating activities |  |  | (1,228 | ) |  |  | 50,840 |  |  |  | — |  |  |  | 49,612 |
Cash flows from investing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital expenditures |  |  | — |  |  |  | (226,544 | ) |  |  | — |  |  |  | (226,544 | )
Acquisition of oil and gas properties |  |  | — |  |  |  | (86,393 | ) |  |  | — |  |  |  | (86,393 | )
Derivative settlements |  |  | — |  |  |  | (120 | ) |  |  | — |  |  |  | (120 | )
Advances to joint interest partners |  |  | — |  |  |  | 1,010 |  |  |  | — |  |  |  | 1,010 |
Advances from joint interest partners |  |  | — |  |  |  | 2,512 |  |  |  | — |  |  |  | 2,512 |
Net cash used in investing activities |  |  | — |  |  |  | (309,535 | ) |  |  | — |  |  |  | (309,535 | )
Cash flows from financing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of common stock |  |  | 399,669 |  |  |  | — |  |  |  | — |  |  |  | 399,669 |
Proceeds from credit facility |  |  | — |  |  |  | 72,000 |  |  |  | — |  |  |  | 72,000 |
Principal payments on credit facility |  |  | — |  |  |  | (107,000 | ) |  |  | — |  |  |  | (107,000 | )
Debt issuance costs |  |  | — |  |  |  | (1,788 | ) |  |  | — |  |  |  | (1,788 | )
Investment in / capital contributions from subsidiaries |  |  | (278,501 | ) |  |  | 278,501 |  |  |  | — |  |  |  | — |
Net cash provided by financing activities |  |  | 121,168 |  |  |  | 241,713 |  |  |  | — |  |  |  | 362,881 |
Increase (decrease) in cash and cash equivalents |  |  | 119,940 |  |  |  | (16,982 | ) |  |  | — |  |  |  | 102,958 |
Cash and cash equivalents at beginning of period |  |  | — |  |  |  | 40,562 |  |  |  | — |  |  |  | 40,562 |
Cash and cash equivalents at end of period |  | $ | 119,940 |  |  | $ | 23,580 |  |  | $ | — |  |  | $ | 143,520 |

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