Acquisitions (Details)	3 Months Ended
Mar. 31, 2019 USD ($) a	Mar. 31, 2018 USD ($)
Nonmonetary Transaction [Line Items]
Carrying value of properties exchanged	$ 65,788,000	$ 0
Howard, Martin, and Midland Counties Trades 2019 [Member]
Nonmonetary Transaction [Line Items]
Net acres exchanged \| a	2,000
Carrying value of properties exchanged	$ 65,800,000
Basis of accounting for assets exchanged	carryover
Gain (loss) recognized on trade	$ 0

Acreage exchanged through non-monetary trades.

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- Definition

The net book value of a nonmonetary asset transferred or exchanged in connection with the acquisition of a business or asset in a noncash transaction. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Nonmonetary assets and liabilities are assets and liabilities that will not result in cash receipts or cash payments in the future.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

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- Definition

Disclosure of the accounting treatment and method of measurement for nonmonetary exchanges of assets or liabilities or related to a transfer of nonmonetary assets for which the Entity receives no assets in return.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 845
-SubTopic 10
-Section 50
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- Definition

Disclosure of the difference in values (gain (loss)) between the nonmonetary assets or liabilities exchanged with another entity inclusive of boot (small monetary consideration).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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