Accounts Receivable Sale Program (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Receivables [Abstract]
Maximum Limit Accounts Receivable Sale Program	$ 120.0
Trade Accounts Receivable Sold	76.4	$ 52.9
Amount Received From Trade Accounts Receivable Sold To Third Party	$ 76.3	$ 52.7

Accounts receivable program with third party maximum amount at any time that can be sold.

No definition available.

Name:	bhe_MaximumLimitAccountsReceivableSaleProgram
Namespace Prefix:	bhe_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration