Document and Entity Information	12 Months Ended
Dec. 31, 2022
Document and Entity Information [Abstract]
Entity Central Index Key	0000842517
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Auditor Name	Rehmann Robson LLC
Auditor Location	Saginaw, Michigan
Auditor Firm ID	263

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

No definition available.

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- Definition

PCAOB issued Audit Firm Identifier

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 10-K
-Number 249
-Section 310

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 20-F
-Number 249
-Section 220
-Subsection f

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 40-F
-Number 249
-Section 240
-Subsection f

+ Details

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- References

+ Details

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Namespace Prefix:	dei_
Data Type:	dei:internationalNameItemType
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Period Type:	duration

- References

+ Details

Name:	dei_AuditorName
Namespace Prefix:	dei_
Data Type:	dei:internationalNameItemType
Balance Type:	na
Period Type:	duration

- Definition

End date of current fiscal year in the format --MM-DD.

+ References

No definition available.

+ Details

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Namespace Prefix:	dei_
Data Type:	xbrli:gMonthDayItemType
Balance Type:	na
Period Type:	duration

- Definition

Fiscal period values are FY, Q1, Q2, and Q3. 1st, 2nd and 3rd quarter 10-Q or 10-QT statements have value Q1, Q2, and Q3 respectively, with 10-K, 10-KT or other fiscal year statements having FY.

+ References

No definition available.

+ Details

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Namespace Prefix:	dei_
Data Type:	dei:fiscalPeriodItemType
Balance Type:	na
Period Type:	duration

- Definition

This is focus fiscal year of the document report in YYYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

+ References

No definition available.

+ Details

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Namespace Prefix:	dei_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

+ Details

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Data Type:	dei:centralIndexKeyItemType
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- Definition

Document and entity information.

+ References

No definition available.

+ Details

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