CONDENSED STATEMENTS OF OPERATIONS [Parenthetical] (USD $)	3 Months Ended	6 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Reimbursements to affiliate (in dollars)	$ 11,343	$ 7,780	$ 24,241	$ 24,071
Limited Partner Units	36,497	36,497	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