Represents the maturity periods of the investments held by the entity.

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Period Type:	instant

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
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Balance Type:	debit
Period Type:	duration

- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
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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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Data Type:	xbrli:stringItemType
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- Details

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Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

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Significant Accounting Policies - Equity Instruments and Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Equity Instruments and Investments
Equity instruments with readily determinable fair value	$ 45,400		$ 45,400		$ 68,200
Non-cash mark-to-market adjustment	0	$ 0	0	$ 0
Equity instruments without readily determinable fair values	305,800		305,800		295,400
Debt securities of our captive insurance companies	$ 32,600		$ 32,600		$ 52,800
Debt Securities \| Securities in captive insurance subsidiary portfolio \| Minimum
Equity Instruments and Investments
Investment maturity period			1 year
Debt Securities \| Securities in captive insurance subsidiary portfolio \| Maximum
Equity Instruments and Investments
Investment maturity period			10 years