Commitments and Contingencies - Additional Information (Details) - USD ($)	3 Months Ended
Jun. 30, 2018	Mar. 31, 2018
Commitments And Contingencies [Line Items]
Minimum lease commitments	$ 158,000,000	$ 162,000,000
Indemnification provisions	0	0
Putnam and Gibson Counties [Member] \| Performance Guarantee [Member]
Commitments And Contingencies [Line Items]
Guarantees of affiliate pollution control and solid waste disposal bonds	$ 100,000,000	100,000,000
TMNA [Member]
Commitments And Contingencies [Line Items]
15-year lease agreement between TMCC and TMNA	15 years
Lease agreement expiration date	Aug. 31, 2032
TMCC-affiliated companies [Member]
Commitments And Contingencies [Line Items]
Minimum lease commitments	$ 103,000,000	$ 105,000,000
TMCC-affiliated companies [Member] \| Putnam and Gibson Counties [Member] \| Performance Guarantee [Member]
Commitments And Contingencies [Line Items]
Guarantees of affiliate pollution control and solid waste disposal bonds	100,000,000
TMCC-affiliated companies [Member] \| Putnam and Gibson Counties [Member] \| Performance Guarantee [Member] \| 2028 [Member]
Commitments And Contingencies [Line Items]
Guarantees of affiliate pollution control and solid waste disposal bonds	20,000,000
TMCC-affiliated companies [Member] \| Putnam and Gibson Counties [Member] \| Performance Guarantee [Member] \| 2029 [Member]
Commitments And Contingencies [Line Items]
Guarantees of affiliate pollution control and solid waste disposal bonds	50,000,000
TMCC-affiliated companies [Member] \| Putnam and Gibson Counties [Member] \| Performance Guarantee [Member] \| 2030 [Member]
Commitments And Contingencies [Line Items]
Guarantees of affiliate pollution control and solid waste disposal bonds	10,000,000
TMCC-affiliated companies [Member] \| Putnam and Gibson Counties [Member] \| Performance Guarantee [Member] \| 2031 [Member]
Commitments And Contingencies [Line Items]
Guarantees of affiliate pollution control and solid waste disposal bonds	10,000,000
TMCC-affiliated companies [Member] \| Putnam and Gibson Counties [Member] \| Performance Guarantee [Member] \| 2032 [Member]
Commitments And Contingencies [Line Items]
Guarantees of affiliate pollution control and solid waste disposal bonds	$ 10,000,000

Commitments and contingencies.

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- Definition

Provision for indemnification.

+ References

No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

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- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717

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