For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 50
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-Subparagraph (a)
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Significant Payors (Narrative) (Details)	3 Months Ended		9 Months Ended		12 Months Ended
Significant Payors (Narrative) (Details)	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Revenues [Member] \| Illinois Department On Aging [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	22.90%	22.10%	23.10%	26.00%
Revenues [Member] \| Geographic Concentration Risk [Member] \| Illinois [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	38.50%	36.40%	37.80%	39.10%
Accounts Receivable [Member] \| Illinois Department On Aging [Member]
Concentration Risk [Line Items]
Concentration risk, percentage			18.50%		25.10%