Fair Value Measurements (Schedule of Fair Value of Assets and Liabilities not Subject to Fair Value Recognition) (Detail) $ in Thousands	Jun. 30, 2020 USD ($)	Dec. 31, 2019
Assets
Notes receivable, Carrying Value	$ 52,100
Fair Value Level 3 [Member]
Assets
Notes receivable, Fair Value	$ 57,300
Real estate appreciation [Member] \| Wellstat Diagnostics [Member]
Fair Value by Balance Sheet Grouping [Line Items]
Loans Held-for-sale, Measurement Input	0	0
Estimated realtor fee [Member] \| Wellstat Diagnostics [Member]
Fair Value by Balance Sheet Grouping [Line Items]
Loans Held-for-sale, Measurement Input	0.06	0.06
Minimum [Member] \| Measurement Input, Discount Rate [Member] \| Wellstat Diagnostics [Member]
Fair Value by Balance Sheet Grouping [Line Items]
Loans Held-for-sale, Measurement Input	0.12	0.12
Maximum [Member] \| Measurement Input, Discount Rate [Member] \| Wellstat Diagnostics [Member]
Fair Value by Balance Sheet Grouping [Line Items]
Loans Held-for-sale, Measurement Input	0.15	0.15

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No definition available.

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Value of input used to measure loan, held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
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Amount, before allowance for credit loss, of financing receivable, classified as noncurrent.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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