Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2420-110228

Name:	us-gaap_AssetImpairmentCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Seismic Data Library (Details) (USD $)	3 Months Ended		6 Months Ended
Seismic Data Library (Details) (USD $)	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jul. 01, 2014
Seismic Data Library [Line Items]
Straight-line amortization period			4 years
Internal data processing costs capitalized	$ 1,000,000	$ 1,000,000	$ 1,900,000	$ 1,900,000
Lowest amortization rate using the income forecast method			70.00%
Actual aggregate rate of amortization					70.00%
Asset impairment charges			$ 0	$ 0