CONDENSED STATEMENTS OF OPERATIONS [Parenthetical] (USD $)	3 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Reimbursements to affiliate (in dollars)	$ 12,898	$ 16,290
Limited Partner Units	(36,497)	(36,497)

The average number of shares or units issued and outstanding that are used in calculating basic and diluted EPS.

No definition available.

Name:	bftcviii_LimitedPartnerUnits
Namespace Prefix:	bftcviii_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration