Summary of Significant Accounting Policies Summary of Significant Accounting Policies:Vendor Rebates and Allowances (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Vendor Rebates and Allowances	$ 11.3	$ 9.7

Rebates and allowances receivable from the vendor as of the balance sheet date.

No definition available.

Name:	bcc_VendorRebatesAndAllowances
Namespace Prefix:	bcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant