Accumulated Depreciation, Depletion and Amortization Property, Plant and Equipment Excluding Rental Equipment

No definition available.

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Namespace Prefix:	fet_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Property, Plant, and Equipment Excluding Rental Equipment, Gross

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Property, Plant and Equipment, Excluding Rental Equipment, Net

+ References

No definition available.

+ Details

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Namespace Prefix:	fet_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.14)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

-Article 5

+ Details

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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

+ Details

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_PropertyPlantAndEquipmentGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

-Subparagraph a

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

+ Details

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- Details

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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Property and equipment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment, Net [Abstract]
Property & equipment, excluding rental equipment, gross	$ 235,128	$ 197,174
Less: accumulated depreciation, excluding rental equipment	(88,526)	(79,343)
Property & equipment, excluding rental equipment, net	146,602	117,831
Property & equipment, net	180,292	152,983
Depreciation expense	36,166	31,458	26,245
Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	3 years
Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	20 years
Land [Member]
Property, Plant and Equipment, Net [Abstract]
Property & equipment, excluding rental equipment, gross	6,718	3,926
Buildings and leasehold improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Property & equipment, excluding rental equipment, gross	53,025	47,390
Buildings and leasehold improvements [Member] \| Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	7 years
Buildings and leasehold improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	20 years
Computer equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property & equipment, excluding rental equipment, gross	29,374	14,227
Computer equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	3 years
Computer equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	5 years
Machinery & equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property & equipment, excluding rental equipment, gross	102,937	94,198
Machinery & equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	5 years
Machinery & equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	10 years
Furniture & fixtures [Member]
Property, Plant and Equipment, Net [Abstract]
Property & equipment, excluding rental equipment, gross	6,625	12,678
Furniture & fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	3 years
Furniture & fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	10 years
Vehicles [Member]
Property, Plant and Equipment, Net [Abstract]
Property & equipment, excluding rental equipment, gross	11,247	11,328
Vehicles [Member] \| Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	3 years
Vehicles [Member] \| Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	5 years
Construction in progress [Member]
Property, Plant and Equipment, Net [Abstract]
Property & equipment, excluding rental equipment, gross	25,202	13,427
Rental equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property & equipment, gross	110,455	105,162
Less: accumulated depreciation	(76,765)	(70,010)
Property & equipment, net	$ 33,690	$ 35,152
Rental equipment [Member] \| Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	3 years
Rental equipment [Member] \| Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Estimated useful life, property and equipment	10 years