XML 122 R99.htm IDEA: XBRL DOCUMENT v3.6.0.2

Supplemental Oil and Gas Disclosures (Unaudited) - Additional Information (Detail) bbl in Thousands, Mcf in Thousands		12 Months Ended
		Dec. 31, 2016 well $ / MMBTU $ / Boe bbl Mcf	Dec. 31, 2015 Boe well	Dec. 31, 2015 Boe $ / MMBTU	Dec. 31, 2015 Boe bbl	Dec. 31, 2015 Boe Mcf	Dec. 31, 2015 Boe $ / Boe	Dec. 31, 2014 Boe well $ / MMBTU $ / Boe bbl Mcf
Supplemental Oil And Gas Reserve Information [Line Items]
New well addition | well		0	36					106
Crude Oil and NGL
Supplemental Oil And Gas Reserve Information [Line Items]
Average spot price | $ / Boe		42.75					50.28	94.99
Natural Gas in Mmbtu
Supplemental Oil And Gas Reserve Information [Line Items]
Average spot price | $ / MMBTU		2.48		2.59				4.35
Consolidated Entities
Supplemental Oil And Gas Reserve Information [Line Items]
Proved developed and undeveloped reserves, revisions of previous estimates								608
Oil | Consolidated Entities
Supplemental Oil And Gas Reserve Information [Line Items]
Proved developed and undeveloped reserves, sales of minerals in place	[1]	4,460			704			105
Proved developed and undeveloped reserves, revisions of previous estimates	[1]	(11)			855			608
Extensions and discoveries (added)	[1]	29			224			2,191
New PDP Reserves | Consolidated Entities
Supplemental Oil And Gas Reserve Information [Line Items]
Extensions and discoveries (added)								694
New PUD Reserves | Consolidated Entities
Supplemental Oil And Gas Reserve Information [Line Items]
Extensions and discoveries (added)								913
Oil Less Natural Gas Liquids | Consolidated Entities
Supplemental Oil And Gas Reserve Information [Line Items]
Proved developed and undeveloped reserves, sales of minerals in place	[1]	4,155
Natural Gas Liquids | Consolidated Entities
Supplemental Oil And Gas Reserve Information [Line Items]
Proved developed and undeveloped reserves, sales of minerals in place		305
Natural Gas | Consolidated Entities
Supplemental Oil And Gas Reserve Information [Line Items]
Proved developed and undeveloped reserves, sales of minerals in place | Mcf		3,756				1,223		218
Proved developed and undeveloped reserves, revisions of previous estimates		631			1,995	1,675		293
Extensions and discoveries (added) | Mcf		0				173		774
BOE
Supplemental Oil And Gas Reserve Information [Line Items]
Proved undeveloped reserve (Energy) | Boe			0	0	0	0	0	2,703,000
[1] Includes natural gas liquids (NGLs).

X

- Definition

Number Of Productive Wells Added During Year

+ References

No definition available.

+ Details

Name:	for_NumberOfProductiveWellsAddedDuringYear
Namespace Prefix:	for_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Supplemental Oil And Gas Reserve Information [Line Items]

+ References

No definition available.

+ Details

Name:	for_SupplementalOilAndGasReserveInformationLineItems
Namespace Prefix:	for_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The revenues derived from sales of oil or gas in each geographic area during the reporting period divided by the number of barrels of oil produced or thousands of cubic feet of gas produced.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1204
-Paragraph (b)
-Subparagraph (1)

+ Details

Name:	us-gaap_AverageSalesPrices
Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Additions to proved reserves that result from (1) extension of the proved acreage of previously discovered (old) reservoirs through additional drilling in periods after discovery and (2) discovery of new fields with proved reserves or of new reservoirs of proved reserves in old fields.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 5
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447

+ Details

Name:	us-gaap_ProvedDevelopedAndUndevelopedReservesExtensionsDiscoveriesAndAdditions
Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Revisions represent changes in previous estimates of proved reserves, either upward or downward, resulting from new information (except for an increase in proved acreage) normally obtained from development drilling and production history or resulting from change in economic factors.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447

+ Details

Name:	us-gaap_ProvedDevelopedAndUndevelopedReservesRevisionsOfPreviousEstimatesIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Sales of minerals in place.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 5
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61831-109447

+ Details

Name:	us-gaap_ProvedDevelopedAndUndevelopedReservesSalesOfMineralsInPlace
Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Energy measure of proved undeveloped reserves of crude oil, including condensate and natural gas liquids, natural gas, synthetic oil and gas, or other nonrenewable natural resource that is intended to be upgraded into synthetic oil and gas.

+ References

No definition available.

+ Details

Name:	us-gaap_ProvedUndevelopedReserveBOE1
Namespace Prefix:	us-gaap_
Data Type:	num:energyItemType
Balance Type:	na
Period Type:	instant

X

- Details

Name:	us-gaap_AverageSalesPriceAndProductionCostsPerUnitOfProductionProductionTypeAxis=us-gaap_CrudeOilAndNGLPerBarrelMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_AverageSalesPriceAndProductionCostsPerUnitOfProductionProductionTypeAxis=for_NaturalGasInMmbtuMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	dei_LegalEntityAxis=us-gaap_ConsolidatedEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ReserveQuantitiesByTypeOfReserveAxis=us-gaap_OilReservesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ReserveQuantitiesByTypeOfReserveAxis=for_NewPDPReservesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ReserveQuantitiesByTypeOfReserveAxis=for_NewPUDReservesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ReserveQuantitiesByTypeOfReserveAxis=for_OilLessNaturalGasLiquidsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ReserveQuantitiesByTypeOfReserveAxis=us-gaap_NaturalGasLiquidsReservesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ReserveQuantitiesByTypeOfReserveAxis=us-gaap_NaturalGasReservesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ReserveQuantitiesByTypeOfReserveAxis=for_BarrelsofOilEquivalentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: