2.4.0.812431402 - Disclosure - Level 4 Retirement and Benefit Plans (Details)truefalsefalse1false USDfalsefalse$D2013Q2http://www.sec.gov/CIK0001328581duration2013-04-01T00:00:002013-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$D2013Q1http://www.sec.gov/CIK0001328581duration2013-01-01T00:00:002013-03-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$D2012Q2http://www.sec.gov/CIK0001328581duration2012-04-01T00:00:002012-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDfalsefalse$D2013Q2SDhttp://www.sec.gov/CIK0001328581duration2013-07-01T00:00:002013-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$5false USDfalsefalse$D2013Q2YTDhttp://www.sec.gov/CIK0001328581duration2013-01-01T00:00:002013-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$6false USDfalsefalse$D2012Q2YTDhttp://www.sec.gov/CIK0001328581duration2012-01-01T00:00:002012-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$7false USDfalsefalse$D2012Q4YTDhttp://www.sec.gov/CIK0001328581duration2012-01-01T00:00:002012-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$8false USDfalsefalse$D2011Q4YTDhttp://www.sec.gov/CIK0001328581duration2011-01-01T00:00:002011-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$9false USDfalsefalse$D2010Q4YTDhttp://www.sec.gov/CIK0001328581duration2010-01-01T00:00:002010-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 2us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Net periodic benefit cost [Abstract]2false 3us-gaap_DefinedBenefitPlanServiceCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse671000671000USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse11820001182000USD$falsetruefalse4falsefalsefalse00falsefalsefalse5truefalsefalse13420001342000USD$falsetruefalse6truefalsefalse23510002351000USD$falsetruefalse7truefalsefalse47620004762000USD$falsetruefalse8truefalsefalse51120005112000USD$falsetruefalse9truefalsefalse49310004931000USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Service Cost (Component of Net Periodic Pension Cost) -URI http://asc.fasb.org/extlink&oid=6525008 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 false2Service cost3false 3us-gaap_DefinedBenefitPlanInterestCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse46500004650000falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse48240004824000falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse92920009292000falsefalsefalse6truefalsefalse96670009667000falsefalsefalse7truefalsefalse1923400019234000falsefalsefalse8truefalsefalse2048400020484000falsefalsefalse9truefalsefalse2025800020258000falsefalsefalsexbrli:monetaryItemTypemonetaryThe increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 false2Interest cost4false 3us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssetsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse-4916000-4916000falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse-4847000-4847000falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse-9782000-9782000falsefalsefalse6truefalsefalse-9691000-9691000falsefalsefalse7truefalsefalse-19390000-19390000falsefalsefalse8truefalsefalse-17910000-17910000falsefalsefalse9truefalsefalse-18474000-18474000falsefalsefalsexbrli:monetaryItemTypemonetaryAn amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512136 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512171 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 false2Expected return on plan assets5false 3us-gaap_DefinedBenefitPlanAmortizationOfGainsLossesus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse22810002281000falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse19580001958000falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse45370004537000falsefalsefalse6truefalsefalse39840003984000falsefalsefalse7truefalsefalse76320007632000falsefalsefalse8truefalsefalse27030002703000falsefalsefalse9truefalsefalse556000556000falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of gains or losses recognized in net periodic benefit cost.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 false2Amortization of actuarial loss6false 3us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCreditus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse2200022000falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse4200042000falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse4500045000falsefalsefalse6truefalsefalse8300083000falsefalsefalse7truefalsefalse165000165000falsefalsefalse8truefalsefalse175000175000falsefalsefalse9truefalsefalse178000178000falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 false2Amortization of prior service costs7false 3us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse27080002708000falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse31590003159000falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse54340005434000falsefalsefalse6truefalsefalse63940006394000falsefalsefalse7truefalsefalse1265300012653000falsefalsefalse8truefalsefalse1136800011368000falsefalsefalse9truefalsefalse74490007449000falsefalsefalsexbrli:monetaryItemTypemonetaryThe total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 true2Net periodic benefit cost8true 2us-gaap_PensionAndOtherPostretirementBenefitContributionsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Pension contributions [Abstract]9false 3us-gaap_PensionContributionsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse93000009300000falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse99700009970000falsefalsefalse6truefalsefalse78740007874000falsefalsefalse7truefalsefalse84860008486000falsefalsefalse8truefalsefalse1362100013621000falsefalsefalse9truefalsefalse38730003873000falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of cash or cash equivalents contributed by the entity to fund its pension plans.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585 false2Pension contributions10false 3us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInCurrentFiscalYearus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse10000001000000USD$falsetruefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.No definition available.false2Estimated remaining 2013 contributionsfalseLevel 4 Retirement and Benefit Plans (Details) (USD $)NoRoundingUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.bc.com/role/Level4RetirementAndBenefitPlansDetailsQuarterEnd910