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_
Data Type:	num:perShareItemType
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://fasb.org/us-gaap/role/ref/legacyRef
-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=120381028&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
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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

Value, before forfeiture, of shares issued under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Details

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Data Type:	na
Balance Type:
Period Type:

Stock-Based Compensation - Restricted Stock Units and Stock Awards Grants (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					4,603	4,381	3,880
Restricted Stock Units and Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	35	52	78	4,438
Shares granted (in dollars per share)	$ 2.91	$ 2.78	$ 3.91	$ 7.06
Total value of restricted shares granted	$ 102	$ 144	$ 303	$ 31,341