Consolidated Statements Of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Consolidated Statements Of Income [Abstract]
Sales	$ 620,925us-gaap_SalesRevenueNet	$ 639,344us-gaap_SalesRevenueNet
Cost of sales	569,146us-gaap_CostOfGoodsAndServicesSold	588,221us-gaap_CostOfGoodsAndServicesSold
Gross profit	51,779us-gaap_GrossProfit	51,123us-gaap_GrossProfit
Selling, general and administrative expenses	28,202	28,153
Restructuring charges and integration costs	4,869	2,109
Thailand flood-related items, net of insurance	0bhe_FloodRelatedItemsNetOfInsurance	(1,571)bhe_FloodRelatedItemsNetOfInsurance
Income from operations	18,708us-gaap_OperatingIncomeLoss	22,432us-gaap_OperatingIncomeLoss
Interest expense	(435)us-gaap_InterestExpense	(476)us-gaap_InterestExpense
Interest income	432us-gaap_InvestmentIncomeInterest	515us-gaap_InvestmentIncomeInterest
Other income (expense)	(1,057)us-gaap_OtherNonoperatingIncomeExpense	26us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	17,648	22,497
Income tax expense	3,443us-gaap_IncomeTaxExpenseBenefit	3,372us-gaap_IncomeTaxExpenseBenefit
Net income	$ 14,205us-gaap_NetIncomeLoss	$ 19,125us-gaap_NetIncomeLoss
Earnings per share:
Basic	$ 0.27us-gaap_EarningsPerShareBasic	$ 0.36us-gaap_EarningsPerShareBasic
Diluted	$ 0.27us-gaap_EarningsPerShareDiluted	$ 0.35us-gaap_EarningsPerShareDiluted
Weighted-average number of shares outstanding:
Basic	52,463	53,650
Diluted	53,045	54,277

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