Earnings Per Share (Details) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Earnings Per Share [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, (in shares)	1.1	0.9	1.2	1.4

The value of securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted earnings per share because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

No definition available.

Name:	bkd_AntidilutiveSecuritiesExcludedFromDilutedNetLossAmount
Namespace Prefix:	bkd_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration