Represents the employer matching contribution of the second level of employee contributions.

No definition available.

Name:	th_DefinedContributionPlanEmployerMatchPercentLevelTwo
Namespace Prefix:	th_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the first level of employee contributions which are matched by the employer.

+ References

No definition available.

+ Details

Name:	th_DefinedContributionPlanEmployerMatchingContributionPercentLevelOne
Namespace Prefix:	th_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the second level of employee contributions which are matched by the employer

+ References

No definition available.

+ Details

Name:	th_DefinedContributionPlanEmployerMatchingContributionPercentLevelTwo
Namespace Prefix:	th_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	th_DefinedContributionPlanMinimumAnnualContributionsPerEmployeePercent
Namespace Prefix:	th_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the vesting period under the 401(k) plan.

+ References

No definition available.

+ Details

Name:	th_DefinedContributionPlanVestingPeriod
Namespace Prefix:	th_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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

- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Retirement Plans (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Retirement Plans (Details) - USD ($) $ in Millions	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Retirement Plans
Minimum percentage of annual eligible compensation by the participants			1.00%
Maximum percentage of annual eligible compensation by the participants			90.00%
Percentage of contribution matched			6.00%
Percentage of contribution, matched 100% by employer			3.00%
Employer match of employee contributions of first 3% of contributions			100.00%
Percentage of contribution, matched 50% by employer			3.00%
Employer match of employee contributions of next 3% of contributions			50.00%
Vesting percentage			20.00%
Vesting period			5 years
Contribution expenses	$ 0.2	$ 0.4	$ 0.5	$ 0.6