Equity securities classified as available-for-sale securities acquired.

No definition available.

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- Definition

Unsecured short-term debt instrument issued by corporations which are highly liquid investments that are readily convertible to know amounts of cash and interest-bearing accounts that typically pay a higher interest rate and are FDIC insured.

+ References

No definition available.

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- Definition

Amount of equity securities categorized neither as held-to-maturity nor as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803

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- Definition

The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 9
-Subparagraph (a)
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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity.

+ References

No definition available.

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- Definition

The cash outflow to acquire equity securities classified as available-for-sale securities, because they are not classified as trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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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.

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Investments (Narrative) (Details) - USD ($)	9 Months Ended
Investments (Narrative) (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016	Dec. 31, 2015	Jan. 31, 2015
Schedule of Investments [Line Items]
Commercial paper and money market investments	$ 372,200,000			$ 433,000,000
Marketable equity securities	382,777,000			$ 350,563,000
Cash paid for new marketable equity securities	48,265,000	$ 135,124,000
Marketable equity securities purchased	47,900,000	135,600,000
Gain on sales of marketable equity securities	6,300,000
Proceeds from sales of marketable equity securities	$ 22,800,000	$ 0
HomeHero [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	20.00%
Residential Home Health Illinois [Member] \| Residential Healthcare Group Inc [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	40.00%
Residential Hospice Illinois [Member] \| Residential Healthcare Group Inc [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	42.50%
Residential and a Michigan hospital joint venture [Member] \| Residential Healthcare Group Inc [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	40.00%		40.00%
Celtic Healthcare Allegheny Health Network Joint Venture [Member] \| Celtic Healthcare [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage	40.00%				40.00%