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Summary of Significant Accounting Policies - Additional Information (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 USD ($) counterparty | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Mar. 31, 2017 USD ($)
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Allowance for doubtful accounts | $ 1,573,000 | $ 1,309,000 |  |
Capitalized interest costs | 12,800,000 | 16,800,000 | $ 18,600,000 |
Amount of capitalized exploratory well costs that have been capitalized for period greater than one year | $ 0 |  |  |
Derivative, number of counterparties | counterparty | 8 |  |  |
Financing Receivable, Recorded Investment, Past Due | $ 0 |  |  |
Cumulative-effect adjustment for adoption of ASU 2016-09 |  | 4,724,000 |  |
1 to 12 months |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Contractual commodity derivative volume, percent | 110.00% |  |  |
13 to 24 months |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Contractual commodity derivative volume, percent | 100.00% |  |  |
25 to 36 months |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Contractual commodity derivative volume, percent | 75.00% |  |  |
37 to 60 months |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Contractual commodity derivative volume, percent | 50.00% |  |  |
Restricted stock awards |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Restricted stock awards vesting period | 3 years |  |  |
Building |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Estimated life of assets | 20 years |  |  |
Salt water disposal facilities, natural gas processing plant and pipelines |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Estimated life of assets | 30 years |  |  |
Furniture, software and equipment | Minimum |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Estimated life of assets | 2 years |  |  |
Furniture, software and equipment | Maximum |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Estimated life of assets | 7 years |  |  |
ASU 2016-09 |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Stock-based compensation related to unrealized excess tax benefits |  |  |  | $ 10,600,000
Retained Earnings [Member] |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Cumulative-effect adjustment for adoption of ASU 2016-09 |  | $ 2,684,000 |  |
Retained Earnings [Member] | ASU 2016-09 |  |  |  |
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |
Cumulative-effect adjustment for adoption of ASU 2016-09 | $ (2,700,000) |  |  |

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