Base rental rate before applicable operating expenses incurred monthly for leased space.

No definition available.

Name:	tess_LeaseAndRentalExpenseBaseRentalRate
Namespace Prefix:	tess_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_LesseeLeaseDescriptionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

Name:	us-gaap_LesseeOperatingLeaseTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918638-209977

+ Details

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

- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

+ Details

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

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=tess_LeasedOfficeSpaceTimoniumMarylandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=tess_LeasedOfficeSpaceHuntValleyMarylandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=tess_LeasedOfficeAndWarehouseSpaceSanAntonioTexasMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Leases - Office space (Details) - USD ($)	12 Months Ended
Leases - Office space (Details) - USD ($)	Mar. 29, 2020	Mar. 31, 2019	Apr. 01, 2018
Leases
Rent expense	$ 3,046,000
Rent expense		$ 3,001,800	$ 3,041,700
Minimum
Leases
Lease term	1 year
Maximum
Leases
Lease term	6 years
Leased office space, Timonium, Maryland \| Minimum
Leases
Base rental rate per month	$ 179,700
Leased office space, Timonium, Maryland \| Maximum
Leases
Base rental rate per month	203,800
Leased office space, Hunt Valley, Maryland \| Minimum
Leases
Base rental rate per month	39,300
Leased office space, Hunt Valley, Maryland \| Maximum
Leases
Base rental rate per month	43,000
Leased office and warehouse space, San Antonio, Texas \| Minimum
Leases
Base rental rate per month	18,600
Leased office and warehouse space, San Antonio, Texas \| Maximum
Leases
Base rental rate per month	$ 19,100