The grant date fair values for purposes of disclosing shares potentially issuable under restricted stock awards on all restricted stock plans and other required information pertaining to awards in the customized range.

No definition available.

+ Details

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Namespace Prefix:	bkd_
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Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Gross value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Details

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Stock-Based Compensation - Restricted Stock Grants (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					2,569	3,141	1,698
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	39	67	71	2,392
Shares granted (in dollars per share)	$ 9.84	$ 13.19	$ 13.11	$ 14.84
Total value of restricted shares granted	$ 377	$ 889	$ 937	$ 35,497