Subsequent Event (Details) - Subsequent Event - Bank of America Credit Agreement - Line of Credit $ in Millions	Aug. 01, 2023 USD ($) qtr
Revolving Loan
Subsequent Event [Line Items]
Borrowing capacity	$ 50.0
Accordion feature, increase limit	$ 25.0
Days prior to maturity date	91 days
Covenant, consecutive quarters \| qtr	4
Revolving Loan \| Secured Overnight Financing Rate (SOFR)
Subsequent Event [Line Items]
Additional basis spread on variable rate	0.10%
Revolving Loan \| Minimum
Subsequent Event [Line Items]
Unused portion of borrowing commitment	0.05%
Revolving Loan \| Minimum \| Secured Overnight Financing Rate (SOFR)
Subsequent Event [Line Items]
Basis spread on variable rate	2.25%
Revolving Loan \| Minimum \| Base rate
Subsequent Event [Line Items]
Basis spread on variable rate	1.25%
Revolving Loan \| Maximum
Subsequent Event [Line Items]
Unused portion of borrowing commitment	0.0625%
Revolving Loan \| Maximum \| Secured Overnight Financing Rate (SOFR)
Subsequent Event [Line Items]
Basis spread on variable rate	2.75%
Revolving Loan \| Maximum \| Base rate
Subsequent Event [Line Items]
Basis spread on variable rate	1.75%
Credit commitments
Subsequent Event [Line Items]
Borrowing capacity	$ 15.0
Swing line
Subsequent Event [Line Items]
Borrowing capacity	$ 5.0

Debt Instrument, Additional Basis Spread on Variable Rate

No definition available.

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Namespace Prefix:	band_
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Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Accordion Feature, Increase Limit

+ References

No definition available.

+ Details

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Namespace Prefix:	band_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Covenant, Consecutive Quarters

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Days Prior to Maturity Date

+ References

No definition available.

+ Details

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Namespace Prefix:	band_
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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
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- 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
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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