Note, Loans nd Financing Receivable, Gross, Current, Loan to Repay Third Party Loan

No definition available.

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- Definition

Notes, Loans and Financing Receivable, Gross, Current, Loan to Purchase Company Common Stock

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Definition

Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16(a)(2))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

+ Details

Name:	us-gaap_LoansPayable
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for a borrowing supported by a written promise to pay an obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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Balance Type:	credit
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- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis=bmi_EmployeeStockOwnershipPlanEsopPlanMember
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Data Type:	na
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Employee Benefit Plans (Employee Savings and Stock Ownership Plan - Debt) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2010
Debt Instrument
Loans payable	$ 900,000us-gaap_LoansPayable			$ 1,500,000us-gaap_LoansPayable
Principal payments	154,000us-gaap_RepaymentsOfNotesPayable	154,000us-gaap_RepaymentsOfNotesPayable	256,000us-gaap_RepaymentsOfNotesPayable
Employee Stock Ownership Plan (ESOP), Plan \| Loans Receivable
Debt Instrument
Loan to repay third party loan				500,000
Additional loan to ESOP				1,000,000
Loans payable	$ 900,000			$ 1,500,000