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Condensed Consolidating Financial Information (Tables) | 3 Months Ended
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Mar. 31, 2012
Condensed Consolidating Financial Information [Abstract] |
Schedule Of Condensed Consolidating Balance Sheet | Condensed Consolidating Balance Sheet (In thousands, except share data)
|  | March 31, 2012 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
ASSETS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 293,434 |  |  | $ | (6,136 | ) |  | $ | — |  |  | $ | 287,298 |
Accounts receivable – oil and gas revenues |  |  | — |  |  |  | 78,455 |  |  |  | — |  |  |  | 78,455 |
Accounts receivable – joint interest partners |  |  | 88 |  |  |  | 70,285 |  |  |  | (3,358 | ) |  |  | 67,015 |
Inventory |  |  | — |  |  |  | 10,422 |  |  |  | — |  |  |  | 10,422 |
Prepaid expenses |  |  | 154 |  |  |  | 1,586 |  |  |  | — |  |  |  | 1,740 |
Advances to joint interest partners |  |  | — |  |  |  | 3,280 |  |  |  | — |  |  |  | 3,280 |
Deferred income taxes |  |  | — |  |  |  | 6,807 |  |  |  | — |  |  |  | 6,807 |
Other current assets |  |  | 8 |  |  |  | 72 |  |  |  | — |  |  |  | 80 |
Total current assets |  |  | 293,684 |  |  |  | 164,771 |  |  |  | (3,358 | ) |  |  | 455,097 |
Property, plant and equipment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Oil and gas properties (successful efforts method) |  |  | — |  |  |  | 1,515,788 |  |  |  | — |  |  |  | 1,515,788 |
Other property and equipment |  |  | — |  |  |  | 38,660 |  |  |  | — |  |  |  | 38,660 |
Less: accumulated depreciation, depletion, amortization and impairment |  |  | — |  |  |  | (215,436 | ) |  |  | — |  |  |  | (215,436 | )
Total property, plant and equipment, net |  |  | — |  |  |  | 1,339,012 |  |  |  | — |  |  |  | 1,339,012 |
Investments in and advances to subsidiaries |  |  | 1,141,459 |  |  |  | — |  |  |  | (1,141,459 | ) |  |  | — |
Derivative instruments |  |  | — |  |  |  | 486 |  |  |  | — |  |  |  | 486 |
Deferred costs and other assets |  |  | 15,262 |  |  |  | 3,553 |  |  |  | — |  |  |  | 18,815 |
Total assets |  | $ | 1,450,405 |  |  | $ | 1,507,822 |  |  | $ | (1,144,817 | ) |  | $ | 1,813,410 |
LIABILITIES AND STOCKHOLDERS' EQUITY |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accounts payable |  | $ | 3,270 |  |  | $ | 604 |  |  | $ | (3,358 | ) |  | $ | 516 |
Advances from joint interest partners |  |  | — |  |  |  | 14,548 |  |  |  | — |  |  |  | 14,548 |
Revenues and production taxes payable |  |  | — |  |  |  | 45,276 |  |  |  | — |  |  |  | 45,276 |
Accrued liabilities |  |  | 50 |  |  |  | 139,663 |  |  |  | — |  |  |  | 139,713 |
Accrued interest payable |  |  | 15,017 |  |  |  | 7 |  |  |  | — |  |  |  | 15,024 |
Derivative instruments |  |  | — |  |  |  | 16,469 |  |  |  | — |  |  |  | 16,469 |
Other current liabilities |  |  | — |  |  |  | 316 |  |  |  | — |  |  |  | 316 |
Total current liabilities |  |  | 18,337 |  |  |  | 216,883 |  |  |  | (3,358 | ) |  |  | 231,862 |
Long-term debt |  |  | 800,000 |  |  |  | — |  |  |  | — |  |  |  | 800,000 |
Asset retirement obligations |  |  | — |  |  |  | 15,664 |  |  |  | — |  |  |  | 15,664 |
Derivative instruments |  |  | — |  |  |  | 6,434 |  |  |  | — |  |  |  | 6,434 |
Deferred income taxes |  |  | (19,021 | ) |  |  | 125,369 |  |  |  | — |  |  |  | 106,348 |
Other liabilities |  |  | — |  |  |  | 2,013 |  |  |  | — |  |  |  | 2,013 |
Total liabilities |  |  | 799,316 |  |  |  | 366,363 |  |  |  | (3,358 | ) |  |  | 1,162,321 |
Stockholders' equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital contributions from affiliates |  |  | — |  |  |  | 1,097,890 |  |  |  | (1,097,890 | ) |  |  | — |
Common stock, $0.01 par value; 300,000,000 shares authorized; 93,136,773 issued and 93,074,949 outstanding |  |  | 922 |  |  |  | — |  |  |  | — |  |  |  | 922 |
Treasury stock, at cost; 61,824 shares |  |  | (1,783 | ) |  |  | — |  |  |  | — |  |  |  | (1,783 | )
Additional paid-in-capital |  |  | 648,964 |  |  |  | 8,743 |  |  |  | (8,743 | ) |  |  | 648,964 |
Retained earnings |  |  | 2,986 |  |  |  | 34,826 |  |  |  | (34,826 | ) |  |  | 2,986 |
Total stockholders' equity |  |  | 651,089 |  |  |  | 1,141,459 |  |  |  | (1,141,459 | ) |  |  | 651,089 |
Total liabilities and stockholders' equity |  | $ | 1,450,405 |  |  | $ | 1,507,822 |  |  | $ | (1,144,817 | ) |  | $ | 1,813,410 |
Condensed 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 |  |  | 88 |  |  |  | 68,808 |  |  |  | (1,628 | ) |  |  | 67,268 |
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 costs and other assets |  |  | 15,742 |  |  |  | 3,683 |  |  |  | — |  |  |  | 19,425 |
Total assets |  | $ | 1,438,513 |  |  | $ | 1,249,377 |  |  | $ | (960,508 | ) |  | $ | 1,727,382 |
LIABILITIES AND STOCKHOLDERS' EQUITY |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Current liabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accounts payable |  | $ | 1,563 |  |  | $ | 12,272 |  |  | $ | (1,628 | ) |  | $ | 12,207 |
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 |  |  | (13,158 | ) |  |  | 106,141 |  |  |  | — |  |  |  | 92,983 |
Other liabilities |  |  | — |  |  |  | 997 |  |  |  | — |  |  |  | 997 |
Total liabilities |  |  | 804,275 |  |  |  | 290,497 |  |  |  | (1,628 | ) |  |  | 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 |  | $ | 1,438,513 |  |  | $ | 1,249,377 |  |  | $ | (960,508 | ) |  | $ | 1,727,382 |
Schedule Of Condensed Consolidating Statement Of Operations | Condensed Consolidating Statement of Operations (In thousands)
|  | Three Months Ended March 31, 2012 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Revenues |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Oil and gas revenues |  | $ | — |  |  | $ | 137,906 |  |  | $ | — |  |  | $ | 137,906 |
Well services revenues |  |  | — |  |  |  | 660 |  |  |  | — |  |  |  | 660 |
Total revenues |  |  | — |  |  |  | 138,566 |  |  |  | — |  |  |  | 138,566 |
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease operating expenses |  |  | — |  |  |  | 9,816 |  |  |  | — |  |  |  | 9,816 |
Well services operating expenses |  |  | — |  |  |  | 477 |  |  |  | — |  |  |  | 477 |
Marketing, transportation and gathering expenses |  |  | — |  |  |  | 2,569 |  |  |  | — |  |  |  | 2,569 |
Production taxes |  |  | — |  |  |  | 13,266 |  |  |  | — |  |  |  | 13,266 |
Depreciation, depletion and amortization |  |  | — |  |  |  | 38,886 |  |  |  | — |  |  |  | 38,886 |
Exploration expenses |  |  | — |  |  |  | 2,835 |  |  |  | — |  |  |  | 2,835 |
Impairment of oil and gas properties |  |  | — |  |  |  | 368 |  |  |  | — |  |  |  | 368 |
General and administrative expenses |  |  | 2,449 |  |  |  | 9,750 |  |  |  | — |  |  |  | 12,199 |
Total expenses |  |  | 2,449 |  |  |  | 77,967 |  |  |  | — |  |  |  | 80,416 |
Operating income (loss) |  |  | (2,449 | ) |  |  | 60,599 |  |  |  | — |  |  |  | 58,150 |
Other income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings in subsidiaries |  |  | 26,264 |  |  |  | — |  |  |  | (26,264 | ) |  |  | — |
Net loss on derivative instruments |  |  | — |  |  |  | (18,586 | ) |  |  | — |  |  |  | (18,586 | )
Interest expense |  |  | (13,414 | ) |  |  | (485 | ) |  |  | — |  |  |  | (13,899 | )
Other income |  |  | 177 |  |  |  | 421 |  |  |  | — |  |  |  | 598 |
Total other income (expense) |  |  | 13,027 |  |  |  | (18,650 | ) |  |  | (26,264 | ) |  |  | (31,887 | )
Income before income taxes |  |  | 10,578 |  |  |  | 41,949 |  |  |  | (26,264 | ) |  |  | 26,263 |
Income tax benefit (expense) |  |  | 5,863 |  |  |  | (15,685 | ) |  |  | — |  |  |  | (9,822 | )
Net income |  | $ | 16,441 |  |  | $ | 26,264 |  |  | $ | (26,264 | ) |  | $ | 16,441 |
Condensed Consolidating Statement of Operations (In thousands)
|  | Three Months Ended March 31, 2011 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Oil and gas revenues |  | $ | — |  |  | $ | 58,744 |  |  | $ | — |  |  | $ | 58,744 |
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease operating expenses |  |  | — |  |  |  | 5,630 |  |  |  | — |  |  |  | 5,630 |
Marketing, transportation and gathering expenses |  |  | — |  |  |  | 312 |  |  |  | — |  |  |  | 312 |
Production taxes |  |  | — |  |  |  | 6,083 |  |  |  | — |  |  |  | 6,083 |
Depreciation, depletion and amortization |  |  | — |  |  |  | 13,812 |  |  |  | — |  |  |  | 13,812 |
Exploration expenses |  |  | — |  |  |  | 32 |  |  |  | — |  |  |  | 32 |
Impairment of oil and gas properties |  |  | — |  |  |  | 1,381 |  |  |  | — |  |  |  | 1,381 |
General and administrative expenses |  |  | 1,263 |  |  |  | 4,687 |  |  |  | — |  |  |  | 5,950 |
Total expenses |  |  | 1,263 |  |  |  | 31,937 |  |  |  | — |  |  |  | 33,200 |
Operating income (loss) |  |  | (1,263 | ) |  |  | 26,807 |  |  |  | — |  |  |  | 25,544 |
Other income (expense) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings in subsidiaries |  |  | (3,170 | ) |  |  | — |  |  |  | 3,170 |  |  |  | — |
Net loss on derivative instruments |  |  | — |  |  |  | (31,666 | ) |  |  | — |  |  |  | (31,666 | )
Interest expense |  |  | (4,941 | ) |  |  | (257 | ) |  |  | — |  |  |  | (5,198 | )
Other income |  |  | 293 |  |  |  | 19 |  |  |  | — |  |  |  | 312 |
Total other income (expense) |  |  | (7,818 | ) |  |  | (31,904 | ) |  |  | 3,170 |  |  |  | (36,552 | )
Loss before income taxes |  |  | (9,081 | ) |  |  | (5,097 | ) |  |  | 3,170 |  |  |  | (11,008 | )
Income tax benefit |  |  | 2,234 |  |  |  | 1,927 |  |  |  | — |  |  |  | 4,161 |
Net loss |  | $ | (6,847 | ) |  | $ | (3,170 | ) |  | $ | 3,170 |  |  | $ | (6,847 | )
Schedule Of Condensed Consolidating Statement Of Cash Flows | Condensed Consolidating Statement of Cash Flows (In thousands)
|  | Three Months Ended March 31, 2012 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Cash flows from operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income |  | $ | 16,441 |  |  | $ | 26,264 |  |  | $ | (26,264 | ) |  | $ | 16,441 |
Adjustments to reconcile net income to net cash provided by (used in) operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  | (26,264 | ) |  |  | — |  |  |  | 26,264 |  |  |  | — |
Depreciation, depletion and amortization |  |  | — |  |  |  | 38,886 |  |  |  | — |  |  |  | 38,886 |
Impairment of oil and gas properties |  |  | — |  |  |  | 368 |  |  |  | — |  |  |  | 368 |
Deferred income taxes |  |  | (5,863 | ) |  |  | 15,685 |  |  |  | — |  |  |  | 9,822 |
Derivative instruments |  |  | — |  |  |  | 18,586 |  |  |  | — |  |  |  | 18,586 |
Stock-based compensation expenses |  |  | 1,591 |  |  |  | — |  |  |  | — |  |  |  | 1,591 |
Debt discount amortization and other |  |  | 480 |  |  |  | 168 |  |  |  | — |  |  |  | 648 |
Working capital and other changes: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in accounts receivable |  |  | — |  |  |  | (27,768 | ) |  |  | 1,730 |  |  |  | (26,038 | )
Change in inventory |  |  | — |  |  |  | (9,641 | ) |  |  | — |  |  |  | (9,641 | )
Change in prepaid expenses |  |  | 155 |  |  |  | (124 | ) |  |  | — |  |  |  | 31 |
Change in other current assets |  |  | 10 |  |  |  | 473 |  |  |  | — |  |  |  | 483 |
Change in accounts payable and accrued liabilities |  |  | 904 |  |  |  | 11,601 |  |  |  | (1,730 | ) |  |  | 10,775 |
Change in other current liabilities |  |  | — |  |  |  | (188 | ) |  |  | — |  |  |  | (188 | )
Change in other liabilities |  |  | — |  |  |  | 1,001 |  |  |  | — |  |  |  | 1,001 |
Net cash provided by (used in) operating activities |  |  | (12,546 | ) |  |  | 75,311 |  |  |  | — |  |  |  | 62,765 |
Cash flows from investing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital expenditures |  |  | — |  |  |  | (269,975 | ) |  |  | — |  |  |  | (269,975 | )
Derivative settlements |  |  | — |  |  |  | (1,291 | ) |  |  | — |  |  |  | (1,291 | )
Redemptions of short-term investments |  |  | 19,994 |  |  |  | — |  |  |  | — |  |  |  | 19,994 |
Advances to joint interest partners |  |  | — |  |  |  | 655 |  |  |  | — |  |  |  | 655 |
Advances from joint interest partners |  |  | — |  |  |  | 5,484 |  |  |  | — |  |  |  | 5,484 |
Net cash provided by (used in) investing activities |  |  | 19,994 |  |  |  | (265,127 | ) |  |  | — |  |  |  | (245,133 | )
Cash flows from financing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchases of treasury stock |  |  | (1,181 | ) |  |  | — |  |  |  | — |  |  |  | (1,181 | )
Debt issuance costs |  |  | — |  |  |  | (25 | ) |  |  | — |  |  |  | (25 | )
Investment in / capital contributions from affiliates |  |  | (156,315 | ) |  |  | 156,315 |  |  |  | — |  |  |  | — |
Net cash provided by (used in) financing activities |  |  | (157,496 | ) |  |  | 156,290 |  |  |  | — |  |  |  | (1,206 | )
Decrease in cash and cash equivalents |  |  | (150,048 | ) |  |  | (33,526 | ) |  |  | — |  |  |  | (183,574 | )
Cash and cash equivalents at beginning of period |  |  | 443,482 |  |  |  | 27,390 |  |  |  | — |  |  |  | 470,872 |
Cash and cash equivalents at end of period |  | $ | 293,434 |  |  | $ | (6,136 | ) |  | $ | — |  |  | $ | 287,298 |
Condensed Consolidating Statement of Cash Flows (In thousands)
|  | Three Months Ended March 31, 2011 |
|  | Parent/ Issuer |  |  | Combined Guarantor Subsidiaries |  |  | Intercompany Eliminations |  |  | Consolidated |
Cash flows from operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | $ | (6,847 | ) |  | $ | (3,170 | ) |  | $ | 3,170 |  |  | $ | (6,847 | )
Adjustments to reconcile net loss to net cash provided by operating activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in earnings of subsidiaries |  |  | 3,170 |  |  |  | — |  |  |  | (3,170 | ) |  |  |  |
Depreciation, depletion and amortization |  |  | — |  |  |  | 13,812 |  |  |  | — |  |  |  | 13,812 |
Impairment of oil and gas properties |  |  | — |  |  |  | 1,381 |  |  |  | — |  |  |  | 1,381 |
Deferred income taxes |  |  | (2,234 | ) |  |  | (1,927 | ) |  |  | — |  |  |  | (4,161 | )
Derivative instruments |  |  | — |  |  |  | 31,666 |  |  |  | — |  |  |  | 31,666 |
Stock-based compensation expenses |  |  | 527 |  |  |  | — |  |  |  | — |  |  |  | 527 |
Debt discount amortization and other |  |  | 188 |  |  |  | 68 |  |  |  | — |  |  |  | 256 |
Working capital and other changes: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in accounts receivable |  |  | — |  |  |  | (7,550 | ) |  |  | 883 |  |  |  | (6,667 | )
Change in inventory |  |  | — |  |  |  | (37 | ) |  |  | — |  |  |  | (37 | )
Change in prepaid expenses |  |  | 118 |  |  |  | 361 |  |  |  | — |  |  |  | 479 |
Change in other current assets |  |  | (113 | ) |  |  | — |  |  |  | — |  |  |  | (113 | )
Change in other assets |  |  | — |  |  |  | (3 | ) |  |  | — |  |  |  | (3 | )
Change in accounts payable and accrued liabilities |  |  | 5,681 |  |  |  | (12,246 | ) |  |  | (883 | ) |  |  | (7,448 | )
Net cash provided by operating activities |  |  | 490 |  |  |  | 22,355 |  |  |  | — |  |  |  | 22,845 |
Cash flows from investing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital expenditures |  |  | — |  |  |  | (91,126 | ) |  |  | — |  |  |  | (91,126 | )
Derivative settlements |  |  | — |  |  |  | (512 | ) |  |  | — |  |  |  | (512 | )
Purchases of short-term investments |  |  | (114,974 | ) |  |  | — |  |  |  | — |  |  |  | (114,974 | )
Advances to joint interest partners |  |  | — |  |  |  | 885 |  |  |  | — |  |  |  | 885 |
Advances from joint interest partners |  |  | — |  |  |  | 4,938 |  |  |  | — |  |  |  | 4,938 |
Net cash used in investing activities |  |  | (114,974 | ) |  |  | (85,815 | ) |  |  | — |  |  |  | (200,789 | )
Cash flows from financing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of senior notes |  |  | 400,000 |  |  |  | — |  |  |  | — |  |  |  | 400,000 |
Purchases of treasury stock |  |  | (559 | ) |  |  | — |  |  |  | — |  |  |  | (559 | )
Debt issuance costs |  |  | (9,650 | ) |  |  | (377 | ) |  |  | — |  |  |  | (10,027 | )
Investment in / capital contributions from subsidiaries |  |  | (49,999 | ) |  |  | 49,999 |  |  |  | — |  |  |  | — |
Net cash provided by financing activities |  |  | 339,792 |  |  |  | 49,622 |  |  |  | — |  |  |  | 389,414 |
Increase (decrease) in cash and cash equivalents |  |  | 225,308 |  |  |  | (13,838 | ) |  |  | — |  |  |  | 211,470 |
Cash and cash equivalents at beginning of period |  |  | 119,940 |  |  |  | 23,580 |  |  |  | — |  |  |  | 143,520 |
Cash and cash equivalents at end of period |  | $ | 345,248 |  |  | $ | 9,742 |  |  | $ | — |  |  | $ | 354,990 |

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