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Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Deferred tax assets: |  |  |
Net operating loss carryforward | $ 164,363 | $ 120,626 | $ 162,073
Oil and gas property basis difference | 3,595 | 151,260 | 386,302
Investment in pass through entities | 8,620 | 12,343 | 27,469
Stock-based compensation expense | 616 | 813 | 2,084
Business energy investment tax credit | 369 | 369 | 369
AMT credit | 0 | 0 | 3,842
Charitable contributions carryover | 269 | 255 | 303
Change in fair value of derivative instruments | 2,761 | 0 | 48,317
Foreign tax credit carryforwards | 2,009 | 2,074 | 2,074
Accrued liabilities | 834 | 285 | 397
ARO liability | 16,923 | 15,897 | 12,107
Non-oil and gas property basis difference | 104 | 171 | 0
State net operating loss carryover | 11,526 | 6,954 | 5,351
Total deferred tax assets | 211,989 | 311,047 | 650,688
Valuation allowance for deferred tax assets | (211,987) | (298,830) | (645,841)
Deferred tax assets, net of valuation allowance | 2 | 12,217 | 4,847
Deferred tax liabilities: |  |  |
Non-oil and gas property basis difference | 0 | 0 | 155
Change in fair value of derivative instruments | 2 | 11,009 | 0
Total deferred tax liabilities | 2 | 11,009 | 155
Net deferred tax asset | $ 0 | $ 1,208 | $ 4,692

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