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v3.20.4

Property and Equipment | 12 Months Ended
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Dec. 31, 2020
Property and Equipment |
Property and Equipment | 4. Property and Equipment Property and equipment (in thousands), together with the related estimated useful lives at December 31, 2020 and 2019, were as follows:
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, | ​ | ​ |
​ |  | 2020 |  | 2019 | ​ | Useful Lives
Land, building and other | ​ | $ | 16,070 | ​ | $ | 16,612 | ​ |  | 3 to 40 years
Recording equipment | ​ |  | 158,619 | ​ |  | 163,564 | ​ |  | 5 to 10 years
Vibrator energy sources | ​ |  | 73,852 | ​ |  | 78,626 | ​ |  | 5 to 15 years
Vehicles | ​ |  | 22,939 | ​ |  | 25,845 | ​ |  | 1.5 to 10 years
​ | ​ |  | 271,480 | ​ |  | 284,647 | ​ | ​ | ​
Less accumulated depreciation | ​ |  | (232,580) | ​ |  | (231,098) | ​ | ​ | ​
Property and equipment, net | ​ | $ | 38,900 | ​ | $ | 53,549 | ​ | ​ | ​
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- Definition The entire disclosure for long-lived, physical asset used in normal conduct of business and not intended for resale. Includes, but is not limited to, work of art, historical treasure, and similar asset classified as collections. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 958 -SubTopic 360 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=120429125&loc=d3e99893-112916 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -URI http://asc.fasb.org/topic&trid=2155823 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 958 -SubTopic 360 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=120429125&loc=SL120174063-112916 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 958 -SubTopic 360 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=120429125&loc=d3e99779-112916 + Details
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