Maximum Range of Target Award for performance share awards under the long-term Relative Measure Program

No definition available.

Name:	b_MaximumRangeOfTargetAwardOfStockPlan
Namespace Prefix:	b_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum Range of Target Award for performance share awards under the long-term Relative Measure Program

+ References

No definition available.

+ Details

Name:	b_MinimumRangeOfTargetAwardOfStockPlan
Namespace Prefix:	b_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Net Income Per Common Share [Line Items]

+ References

No definition available.

+ Details

Name:	b_NetIncomePerCommonShareLineItems
Namespace Prefix:	b_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Performance Period

+ References

No definition available.

+ Details

Name:	b_SharebasedCompensationArrangementbySharebasedPaymentAwardPerformancePeriod
Namespace Prefix:	b_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

+ Details

Name:	us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

+ Details

Name:	us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Net Income Per Common Share (Details) - shares	1 Months Ended	3 Months Ended		6 Months Ended
Net Income Per Common Share (Details) - shares	Feb. 28, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net Income Per Common Share [Line Items]
Weighted average number of diluted shares outstanding adjustment (in shares)		553,938	544,960	552,467	507,987
Stock Options [Member]
Net Income Per Common Share [Line Items]
Antidilutive securities excluded from computation of EPS		139,307	0	146,607	88,891
Options, granted (in shares)	102,400
Restricted Stock Units (RSUs) [Member]
Net Income Per Common Share [Line Items]
Other than options, granted (in shares)	88,543
Performance Share Awards [Member]
Net Income Per Common Share [Line Items]
Other than options, granted (in shares)	70,005
Performance period				3 years
Minimum range of target award of stock plan				0.00%
Maximum range of target award of stock plan				250.00%