Percentage of one step-down the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

percentage of one step-up the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the ratio of consolidated adjusted earnings before interest, taxes, depreciation and amortization to fixed charge, which is necessary to be maintained under the terms of the debt convents.

+ References

No definition available.

+ Details

Name:	th_DebtInstrumentCovenantConsolidatedFixedChargeCoverageRatio
Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the ratio of total debt to consolidated adjusted earnings before interest, taxes, depreciation and amortization allowed under the terms of the debt convents.

+ References

No definition available.

+ Details

Name:	th_DebtInstrumentCovenantConsolidatedLeverageRatio
Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maintain the ratios when the excess availability reaches the minimum described in the agreement.

+ References

No definition available.

+ Details

Name:	th_LineOfCreditFacilityBorrowingBase
Namespace Prefix:	th_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maintain the ratios when the excess availability reaches the minimum described in the agreement.

+ References

No definition available.

+ Details

Name:	th_LineOfCreditFacilityBorrowingBaseLineCapPercent
Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Option to increase Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

No definition available.

+ Details

Name:	th_LineOfCreditFacilityOptionToIncreaseMaximumBorrowingCapacity
Namespace Prefix:	th_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage of net book value of borrowers' eligible accounts receivables.

+ References

No definition available.

+ Details

Name:	th_PercentageOfNetBookValueOfBorrowersEligibleAccountsReceivable
Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of net book value of borrowers' eligible rental equipment.

+ References

No definition available.

+ Details

Name:	th_PercentageOfNetBookValueOfBorrowersEligibleRentalEquipment
Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of net orderly liquidation value of borrowers' eligible rental equipment.

+ References

No definition available.

+ Details

Name:	th_PercentageOfNetOrderlyLiquidationValueOfBorrowersEligibleRentalEquipment
Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of voting equity interests in non-US restricted subsidiary pledge.

+ References

No definition available.

+ Details

Name:	th_PercentageOfVotingEquityInterestInNonUsRestrictedSubsidiaryPledged
Namespace Prefix:	th_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

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

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_StandbyLettersOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=th_SwinglineLoanMember
Namespace Prefix:
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Debt - ABL Facility (Details) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
Debt - ABL Facility (Details) - USD ($) $ in Thousands	Mar. 15, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
ABL Facility
Proceeds from line of credit			$ 108,240	$ 59,550	$ 1,994
New ABL Facility
ABL Facility
Borrowing capacity	$ 125,000
Proceeds from line of credit	$ 40,000	$ 40,000	$ 40,000
Borrowing base, line cap (as a percent)	12.50%
Applicable margin - one step-down (as a percent)	0.25%
Applicable margin - one step-up (as a percent)	0.25%
Percentage of net book value of borrowers' eligible accounts receivables	85.00%
Percentage of net book value of borrowers' eligible rental equipment	95.00%
Percentage of net orderly liquidation value of borrowers' eligible rental equipment	85.00%
Options to increase commitments	$ 75,000
Percentage of voting equity interests in non-US restricted subsidiary pledge	65.00%
Minimum fixed charge coverage ratio	100.00%
Maximum total net leverage ratio	400.00%
Borrowing base	$ 15,625
Line cap (as a percent)	12.50%
New ABL Facility \| Libor
ABL Facility
Variable rate (as a percent)	2.50%
New ABL Facility \| Base rate
ABL Facility
Variable rate (as a percent)	1.50%
Standby letters of credit
ABL Facility
Borrowing capacity	$ 15,000
Swingline
ABL Facility
Borrowing capacity	$ 15,000