Other Assets - Allowance For Credit Losses Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized for notes receivables in nonaccrual status	$ 0	$ 0	$ 0	$ 0
Prepaid expense	10,900,000		10,900,000		$ 6,100,000
Notes Receivable
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual notes receivable without related allowance for credit loss	0		0		0
Notes receivable 90 days or more past due still accruing	$ 0		$ 0		$ 0

Amount of interest income on financing receivable on nonaccrual status.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of financing receivable on nonaccrual status with no allowance for credit loss.

+ References

+ Details

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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

Amount of financing receivable 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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+ Details

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Balance Type:	debit
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- Definition

Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 942
-SubTopic 210
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-Paragraph 1
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+ Details

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- Details

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