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Consolidating Financial Statements (Tables) | 12 Months Ended
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Dec. 31, 2013
Schedule of Consolidating Balance Sheet | Consolidating Balance Sheet (In thousands, except share data)
| December 31, 2013
| Parent/ Issuer |  | Combined Guarantor Subsidiaries |  | Intercompany Eliminations |  | Consolidated
ASSETS |  |  |  |  |  |  |
Current assets |  |  |  |  |  |  |
Cash and cash equivalents | $ | 34,277 |  |  | $ | 57,624 |  |  | $ | — |  |  | $ | 91,901 |
Accounts receivable – oil and gas revenues | — |  |  | 175,653 |  |  | — |  |  | 175,653 |
Accounts receivable – joint interest partners | — |  |  | 139,459 |  |  | — |  |  | 139,459 |
Accounts receivable – affiliates | 770 |  |  | 9,100 |  |  | (9,870 | ) |  | — |
Inventory | — |  |  | 20,652 |  |  | — |  |  | 20,652 |
Prepaid expenses | 318 |  |  | 9,873 |  |  | — |  |  | 10,191 |
Advances to joint interest partners | — |  |  | 760 |  |  | — |  |  | 760 |
Derivative instruments | — |  |  | 2,264 |  |  | — |  |  | 2,264 |
Deferred income taxes | — |  |  | 6,335 |  |  | — |  |  | 6,335 |
Other current assets | — |  |  | 391 |  |  | — |  |  | 391 |
Total current assets | 35,365 |  |  | 422,111 |  |  | (9,870 | ) |  | 447,606 |
Property, plant and equipment |  |  |  |  |  |  |
Oil and gas properties (successful efforts method) | — |  |  | 4,528,958 |  |  | — |  |  | 4,528,958 |
Other property and equipment | — |  |  | 188,468 |  |  | — |  |  | 188,468 |
Less: accumulated depreciation, depletion, amortization and impairment | — |  |  | (637,676 | ) |  | — |  |  | (637,676 | )
Total property, plant and equipment, net | — |  |  | 4,079,750 |  |  | — |  |  | 4,079,750 |
Assets held for sale | — |  |  | 137,066 |  |  | — |  |  | 137,066 |
Investments in and advances to subsidiaries | 3,450,668 |  |  | — |  |  | (3,450,668 | ) |  | — |
Derivative instruments | — |  |  | 1,333 |  |  | — |  |  | 1,333 |
Deferred income taxes | 85,288 |  |  | — |  |  | (85,288 | ) |  | — |
Deferred costs and other assets | 33,983 |  |  | 12,186 |  |  | — |  |  | 46,169 |
Total assets | $ | 3,605,304 |  |  | $ | 4,652,446 |  |  | $ | (3,545,826 | ) |  | $ | 4,711,924 |
LIABILITIES AND STOCKHOLDERS’ EQUITY |  |  |  |  |  |  |
Current liabilities |  |  |  |  |  |  |
Accounts payable | $ | — |  |  | $ | 8,920 |  |  | $ | — |  |  | $ | 8,920 |
Accounts payable – affiliates | 9,100 |  |  | 770 |  |  | (9,870 | ) |  | — |
Advances from joint interest partners | — |  |  | 12,829 |  |  | — |  |  | 12,829 |
Revenues and production taxes payable | — |  |  | 146,741 |  |  | — |  |  | 146,741 |
Accrued liabilities | 33 |  |  | 241,797 |  |  | — |  |  | 241,830 |
Accrued interest payable | 47,622 |  |  | 288 |  |  | — |  |  | 47,910 |
Derivative instruments | — |  |  | 8,188 |  |  | — |  |  | 8,188 |
Total current liabilities | 56,755 |  |  | 419,533 |  |  | (9,870 | ) |  | 466,418 |
Long-term debt | 2,200,000 |  |  | 335,570 |  |  | — |  |  | 2,535,570 |
Asset retirement obligations | — |  |  | 35,918 |  |  | — |  |  | 35,918 |
Derivative instruments | — |  |  | 139 |  |  | — |  |  | 139 |
Deferred income taxes | — |  |  | 408,435 |  |  | (85,288 | ) |  | 323,147 |
Other liabilities | — |  |  | 2,183 |  |  | — |  |  | 2,183 |
Total liabilities | 2,256,755 |  |  | 1,201,778 |  |  | (95,158 | ) |  | 3,363,375 |
Stockholders’ equity |  |  |  |  |  |  |
Capital contributions from affiliates | — |  |  | 2,930,978 |  |  | (2,930,978 | ) |  | — |
Common stock, $0.01 par value; 300,000,000 shares authorized; 100,866,589 shares issued | 996 |  |  | — |  |  | — |  |  | 996 |
Treasury stock, at cost; 167,155 shares | (5,362 | ) |  | — |  |  | — |  |  | (5,362 | )
Additional paid-in-capital | 985,023 |  |  | 8,743 |  |  | (8,743 | ) |  | 985,023 |
Retained earnings | 367,892 |  |  | 510,947 |  |  | (510,947 | ) |  | 367,892 |
Total stockholders’ equity | 1,348,549 |  |  | 3,450,668 |  |  | (3,450,668 | ) |  | 1,348,549 |
Total liabilities and stockholders’ equity | $ | 3,605,304 |  |  | $ | 4,652,446 |  |  | $ | (3,545,826 | ) |  | $ | 4,711,924 |
Condensed 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 | 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 |
Schedule of Consolidating Statement of Operations | Consolidating Statement of Operations (In thousands)
| Year Ended December 31, 2013
| Parent/ Issuer |  | Combined Guarantor Subsidiaries |  | Intercompany Eliminations |  | Consolidated
Revenues |  |  |  |  |  |  |
Oil and gas revenues | $ | — |  |  | $ | 1,084,412 |  |  | $ | — |  |  | $ | 1,084,412 |
Well services and midstream revenues | — |  |  | 57,587 |  |  | — |  |  | 57,587 |
Total revenues | — |  |  | 1,141,999 |  |  | — |  |  | 1,141,999 |
Expenses |  |  |  |  |  |  |
Lease operating expenses | — |  |  | 94,634 |  |  | — |  |  | 94,634 |
Well services and midstream operating expenses | — |  |  | 30,713 |  |  | — |  |  | 30,713 |
Marketing, transportation and gathering expenses | — |  |  | 25,924 |  |  | — |  |  | 25,924 |
Production taxes | — |  |  | 100,537 |  |  | — |  |  | 100,537 |
Depreciation, depletion and amortization | — |  |  | 307,055 |  |  | — |  |  | 307,055 |
Exploration expenses | — |  |  | 2,260 |  |  | — |  |  | 2,260 |
Impairment of oil and gas properties | — |  |  | 1,168 |  |  | — |  |  | 1,168 |
General and administrative expenses | 14,044 |  |  | 61,266 |  |  | — |  |  | 75,310 |
Total expenses | 14,044 |  |  | 623,557 |  |  | — |  |  | 637,601 |
Operating income (loss) | (14,044 | ) |  | 518,442 |  |  | — |  |  | 504,398 |
Other income (expense) |  |  |  |  |  |  |
Equity in earnings of subsidiaries | 299,459 |  |  | — |  |  | (299,459 | ) |  | — |
Net loss on derivative instruments | — |  |  | (35,432 | ) |  | — |  |  | (35,432 | )
Interest expense, net of capitalized interest | (99,663 | ) |  | (7,502 | ) |  | — |  |  | (107,165 | )
Other income (expense) | (335 | ) |  | 1,551 |  |  | — |  |  | 1,216 |
Total other income (expense) | 199,461 |  |  | (41,383 | ) |  | (299,459 | ) |  | (141,381 | )
Income before income taxes | 185,417 |  |  | 477,059 |  |  | (299,459 | ) |  | 363,017 |
Income tax benefit (expense) | 42,542 |  |  | (177,600 | ) |  | — |  |  | (135,058 | )
Net income | $ | 227,959 |  |  | $ | 299,459 |  |  | $ | (299,459 | ) |  | $ | 227,959 |
Condensed Consolidating Statement of Operations (In thousands)
| Year 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 expenses | — |  |  | 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 |
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, net of capitalized interest | (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 |
Condensed Consolidating Statement of Operations (In thousands)
| Year 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, net of capitalized interest | (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 |
Schedule of Consolidating Statement of Cash Flows | onsolidating Statement of Cash Flows (In thousands)
| Year Ended December 31, 2013
| Parent/ Issuer |  | Combined Guarantor Subsidiaries |  | Intercompany Eliminations |  | Consolidated
Cash flows from operating activities: |  |  |  |  |  |  |
Net income | $ | 227,959 |  |  | $ | 299,459 |  |  | $ | (299,459 | ) |  | $ | 227,959 |
Adjustments to reconcile net income to net cash provided by (used in) operating activities: |  |  |  |  |  |  |
Equity in earnings of subsidiaries | (299,459 | ) |  | — |  |  | 299,459 |  |  | — |
Depreciation, depletion and amortization | — |  |  | 307,055 |  |  | — |  |  | 307,055 |
Impairment of oil and gas properties | — |  |  | 1,168 |  |  | — |  |  | 1,168 |
Deferred income taxes | (42,542 | ) |  | 177,125 |  |  | — |  |  | 134,583 |
Derivative instruments | — |  |  | 35,432 |  |  | — |  |  | 35,432 |
Stock-based compensation expenses | 11,602 |  |  | 380 |  |  | — |  |  | 11,982 |
Debt discount amortization and other | 4,018 |  |  | 230 |  |  | — |  |  | 4,248 |
Working capital and other changes: |  |  |  |  |  |  |
Change in accounts receivable | (460 | ) |  | (110,266 | ) |  | 3,253 |  |  | (107,473 | )
Change in inventory | — |  |  | (13,941 | ) |  | — |  |  | (13,941 | )
Change in prepaid expenses | (5 | ) |  | (8,186 | ) |  | — |  |  | (8,191 | )
Change in other current assets | 235 |  |  | (291 | ) |  | — |  |  | (56 | )
Change in other assets | — |  |  | (3,248 | ) |  | — |  |  | (3,248 | )
Change in accounts payable and accrued liabilities | 20,710 |  |  | 89,994 |  |  | (3,253 | ) |  | 107,451 |
Change in other liabilities | — |  |  | 887 |  |  | — |  |  | 887 |
Net cash provided by (used in) operating activities | (77,942 | ) |  | 775,798 |  |  | — |  |  | 697,856 |
Cash flows from investing activities: |  |  |  |  |  |  |
Capital expenditures | — |  |  | (893,524 | ) |  | — |  |  | (893,524 | )
Acquisition of oil and gas properties | — |  |  | (1,560,072 | ) |  | — |  |  | (1,560,072 | )
Derivative settlements | — |  |  | (8,133 | ) |  | — |  |  | (8,133 | )
Redemptions of short-term investments | 25,000 |  |  | — |  |  | — |  |  | 25,000 |
Advances from joint interest partners | — |  |  | (8,347 | ) |  | — |  |  | (8,347 | )
Net cash provided by (used in) investing activities | 25,000 |  |  | (2,470,076 | ) |  | — |  |  | (2,445,076 | )
Cash flows from financing activities: |  |  |  |  |  |  |
Proceeds from issuance of senior notes | 1,000,000 |  |  | — |  |  | — |  |  | 1,000,000 |
Proceeds from revolving credit facility | — |  |  | 600,000 |  |  | — |  |  | 600,000 |
Principal payments on revolving credit facility | — |  |  | (264,430 | ) |  | — |  |  | (264,430 | )
Debt issuance costs | (16,362 | ) |  | (6,548 | ) |  | — |  |  | (22,910 | )
Proceeds from sale of common stock | 314,580 |  |  | — |  |  | — |  |  | 314,580 |
Purchases of treasury stock | (1,566 | ) |  | — |  |  | — |  |  | (1,566 | )
Investment in / capital contributions from subsidiaries | (1,343,230 | ) |  | 1,343,230 |  |  | — |  |  | — |
Net cash provided by (used in) financing activities | (46,578 | ) |  | 1,672,252 |  |  | — |  |  | 1,625,674 |
Decrease in cash and cash equivalents | (99,520 | ) |  | (22,026 | ) |  | — |  |  | (121,546 | )
Cash and cash equivalents at beginning of period | 133,797 |  |  | 79,650 |  |  | — |  |  | 213,447 |
Cash and cash equivalents at end of period | $ | 34,277 |  |  | $ | 57,624 |  |  | $ | — |  |  | $ | 91,901 |
Condensed 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 | — |  |  | (1,051,365 | ) |  | — |  |  | (1,051,365 | )
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 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 |
Debt issuance costs | (7,307 | ) |  | (705 | ) |  | — |  |  | (8,012 | )
Purchases of treasury stock | (3,194 | ) |  | — |  |  | — |  |  | (3,194 | )
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 |
Condensed 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 | — |  |  | (613,720 | ) |  | — |  |  | (613,720 | )
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 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 |
Debt issuance costs | (16,838 | ) |  | (1,842 | ) |  | — |  |  | (18,680 | )
Purchases of treasury stock | (602 | ) |  | — |  |  | — |  |  | (602 | )
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 |

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