XML 133 R113.htm IDEA: XBRL DOCUMENT
v3.20.4

Supplemental Information on Natural Gas and Oil Exploration, Development and Production Activities (Unaudited) - Capitalized Costs and Accumulated Depreciation, Depletion and Amortization (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Natural gas and oil properties: |  |  |  |  |  |
Properties subject to depletion | [1] | $ 8,891,348 | $ 9,345,557 |  | $ 10,974,929 |
Unproved properties | [1] | 859,766 | 868,180 |  | 2,110,277 |
Total | [1] | 9,751,114 | 10,213,737 |  | 13,085,206 |
Accumulated depreciation, depletion and amortization |  | (4,064,305) | (4,172,702) | [1] | (4,062,021) | [1]
Natural gas and oil properties, successful efforts method, net | [1] | $ 5,686,809 | $ 6,041,035 |  | $ 9,023,185 |
[1] | Includes capitalized asset retirement costs and the associated accumulated amortization.

X
- References No definition available. + Details
Name: | us-gaap_OilAndGasPropertyAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of accumulated depreciation, depletion and amortization of oil and gas property carried under the successful effort method. Oil and gas property include, but not limited to, the entity's wells and related equipment and facilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10.(b)) -URI http://asc.fasb.org/extlink&oid=120398226&loc=d3e511914-122862 + Details
Name: | us-gaap_OilAndGasPropertySuccessfulEffortMethodAccumulatedDepreciationDepletionAndAmortization
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Oil and Gas properties, gross, carried under the successful effort method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10.(b)) -URI http://asc.fasb.org/extlink&oid=120398226&loc=d3e511914-122862 + Details
Name: | us-gaap_OilAndGasPropertySuccessfulEffortMethodGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Oil and gas properties net of accumulated depreciation, depletion, amortization, impairment, and abandonment, carried under the successful effort method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10.(b)) -URI http://asc.fasb.org/extlink&oid=120398226&loc=d3e511914-122862 + Details
Name: | us-gaap_OilAndGasPropertySuccessfulEffortMethodNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Oil and Gas properties with proved reserves under the successful effort method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -URI http://asc.fasb.org/subtopic&trid=2145654 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 25 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=96866604&loc=d3e64746-109465 + Details
Name: | us-gaap_ProvedOilAndGasPropertySuccessfulEffortMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Oil and Gas properties with unproved reserves under the successful effort method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section 25 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=96866604&loc=d3e64746-109465 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61926-109447 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -URI http://asc.fasb.org/topic&trid=2145477 + Details
Name: | us-gaap_UnprovedOilAndGasPropertySuccessfulEffortMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant