v3.3.1.900

Disclosures About Oil and Gas Producing Activities - Summary of Changes in Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Oil and Natural Gas Reserves (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Extractive Industries [Abstract] |  |  |
Standardized measure of discounted future net cash flows, Beginning balance | $ 1,055,815 | $ 676,277 | $ 494,220
Net change in sales and transfer prices and in production (lifting) costs related to future production | (1,405,864) | (59,920) | 74,088
Changes in estimated future development costs | 231,900 | (388,772) | (301,132)
Sales and transfers of oil and gas produced during the period | (91,278) | (209,893) | (149,310)
Net change due to extensions, discoveries and improved recovery | 156,783 | 534,231 | 360,080
Net change due to purchase of minerals in place |  |  | 1,435
Net change due to revisions in quantity estimates | (59,305) | (78,801) | (61,931)
Previously estimated development costs incurred during the period | 146,237 | 382,995 | 287,898
Accretion of discount | 105,582 | 113,188 | 87,937
Other | 6,915 | (11,897) | 1,896
Net change in income taxes | 313,610 | 98,407 | (118,904)
Standardized Measure of discounted future net cash flows | $ 460,395 | $ 1,055,815 | $ 676,277

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- Definition Amount of increase (decrease) in standardized measure of discounted future net cash flow as a result of passage of time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 35 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e62500-109447 + Details
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