XML 91 R77.htm IDEA: XBRL DOCUMENT v3.10.0.1

Commitments and Contingencies - Contingencies (Details) - 6 months ended Jun. 30, 2018 $ in Millions, $ in Billions	AUD ($)	USD ($)
Maximum | Monto Coal Pty Limited
Loss Contingency [Abstract]
Damages sought, value	$ 1.8
Berenergy Corporation vs. the Company | Berenergy
Loss Contingency [Abstract]
Loss contingency accrual		$ 13.1

X

- References

No definition available.

+ Details

Name:	us-gaap_LossContingencyAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

+ Details

Name:	us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

+ Details

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

X

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=btu_MontoCoalPtyLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LitigationCaseAxis=btu_BerenergyCorporationvs.theCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=btu_BerenergyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: