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Supplemental Information On Oil And Gas Exploration And Production Activities (Unaudited) (Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves) (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
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Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] |  |  |
Future cash flows | $ 3,043,450 | $ 4,667,678 | $ 1,657,708
Future development and abandonment costs | (877,660) | (719,898) | (272,500)
Future production costs | (941,243) | (880,427) | (274,428)
Future production taxes | (58,169) | (71,229) | (78,647)
Future income taxes | (2,648) | (693,154) | (172,691)
Future net cash flows | 1,163,730 | 2,302,970 | 859,442
10% discount to reflect timing of cash flows | (399,399) | (875,803) | (280,976)
Standardized measure of discounted future net cash flows | 764,331 | 1,427,167 | 578,466
Diamondback Energy, Inc |  |  |
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] |  |  |
Future cash flows | 0 | 0 | 331,505
Future development and abandonment costs | 0 | 0 | (37,229)
Future production costs | 0 | 0 | (58,096)
Future production taxes | 0 | 0 | (22,925)
Future income taxes | 0 | 0 | (48,547)
Future net cash flows | 0 | 0 | 164,708
10% discount to reflect timing of cash flows | 0 | 0 | (94,462)
Standardized measure of discounted future net cash flows | 0 | 0 | 70,246
Investment in Grizzly Oil Sands ULC |  |  |
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] |  |  |
Future cash flows | 0 | 754,720 | 0
Future development and abandonment costs | 0 | (205,242) | 0
Future production costs | 0 | (291,988) | 0
Future production taxes | 0 | 0 | 0
Future income taxes | 0 | (11,250) | 0
Future net cash flows | $ 0 | 246,240 | 0
10% discount to reflect timing of cash flows |  | (152,494) | 0
Standardized measure of discounted future net cash flows | $ 0 | $ 93,746 | $ 0

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- Definition Amount of estimated future accumulated cash inflow from the sale of proved oil and gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e62424-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e62479-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e62455-109447 + Details
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- Definition Amount of estimated future accumulated cash outflow for costs to be incurred in developing proved oil and gas reserves. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e62424-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 31 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e62455-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=51678428&loc=d3e62479-109447 + Details
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