Supplemental Guarantors Consolidating Condensed Financial Information - Statement of Cash Flows (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net cash provided by (used in) operating activities	$ 18,935	$ 20,854
Cash flows from investing activities:
Cash invested in seismic data	(13,991)	(16,101)
Cash paid to acquire property and equipment	(173)	(250)
Cash from sale of seismic data and property and equipment	58	3
Advances to Seitel Holdings, Inc.	(7)	(8)
Net cash used in investing activities	(14,113)	(16,356)
Cash flows from financing activities:
Principal payments on capital lease obligations	(138)	(112)
Intercompany transfers	0	0
Net cash used in financing activities	(138)	(112)
Effect of exchange rate changes	(112)	460
Net increase in cash and cash equivalents	4,572	4,846
Cash and cash equivalents at beginning of period	70,581	55,997
Cash and cash equivalents at end of period	75,153	60,843
Consolidation, Eliminations [Member]
Cash flows from operating activities:
Net cash provided by (used in) operating activities	0	0
Cash flows from investing activities:
Cash invested in seismic data	0	0
Cash paid to acquire property and equipment	0	0
Cash from sale of seismic data and property and equipment	0	0
Advances to Seitel Holdings, Inc.	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities:
Principal payments on capital lease obligations	0	0
Intercompany transfers	0	0
Net cash used in financing activities	0	0
Effect of exchange rate changes	0	0
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Parent [Member] \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by (used in) operating activities	(12,127)	(12,220)
Cash flows from investing activities:
Cash invested in seismic data	0	0
Cash paid to acquire property and equipment	0	0
Cash from sale of seismic data and property and equipment	0	0
Advances to Seitel Holdings, Inc.	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities:
Principal payments on capital lease obligations	0	0
Intercompany transfers	12,127	12,220
Net cash used in financing activities	12,127	12,220
Effect of exchange rate changes	0	0
Net increase in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by (used in) operating activities	30,125	17,498
Cash flows from investing activities:
Cash invested in seismic data	(9,154)	(9,491)
Cash paid to acquire property and equipment	(141)	(149)
Cash from sale of seismic data and property and equipment	32	0
Advances to Seitel Holdings, Inc.	(7)	(8)
Net cash used in investing activities	(9,270)	(9,648)
Cash flows from financing activities:
Principal payments on capital lease obligations	0	0
Intercompany transfers	(12,056)	(12,220)
Net cash used in financing activities	(12,056)	(12,220)
Effect of exchange rate changes	(1)	0
Net increase in cash and cash equivalents	8,798	(4,370)
Cash and cash equivalents at beginning of period	43,380	47,971
Cash and cash equivalents at end of period	52,178	43,601
Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Cash flows from operating activities:
Net cash provided by (used in) operating activities	937	15,576
Cash flows from investing activities:
Cash invested in seismic data	(4,837)	(6,610)
Cash paid to acquire property and equipment	(32)	(101)
Cash from sale of seismic data and property and equipment	26	3
Advances to Seitel Holdings, Inc.	0	0
Net cash used in investing activities	(4,843)	(6,708)
Cash flows from financing activities:
Principal payments on capital lease obligations	(138)	(112)
Intercompany transfers	(71)	0
Net cash used in financing activities	(209)	(112)
Effect of exchange rate changes	(111)	460
Net increase in cash and cash equivalents	(4,226)	9,216
Cash and cash equivalents at beginning of period	27,201	8,026
Cash and cash equivalents at end of period	$ 22,975	$ 17,242

The cash outflow associated with creating, acquiring or purchasing seismic data (capital expenditure).

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Intercompany Transfer, Financing Activities

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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- Definition

The cash outflow from advancing money to an affiliate (an entity that is related but not strictly controlled by the entity).

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt and payment of capital lease obligations.

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