Contractual Maturities Of Debt securities, Available-for-sale, Range End (In Years)

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- Definition

Contractual Maturities Of Debt securities, Available-for-sale, Range Start (In Years)

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- Definition

Restricted available for sale securities, allowance for credit losses

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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

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

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Amount of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from sale.

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

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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.

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4. Restricted Marketable Securities (Details) - Available for sale - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost		$ 494,000		$ 811,277
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		564		747
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		360		518
Marketable Securities, Allowance for Credit Loss	$ 0	124		0
Restricted marketable securities		253,236		223,785
Restricted available for sale securities, allowance for credit losses [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss, Beginning Balance	0
Cumulative effect adjustment for the adoption of ASU 2016-13				(9,213)
Debt Securities, Available-for-sale, Allowance for Credit Loss, Period Increase (Decrease)	204
Debt Securities, Available-for-sale, Allowance for Credit Loss, Securities Sold	(287)
Debt Securities, Available-for-sale, Allowance for Credit Loss, Ending Balance	124
Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost		243,367		229,199
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		9,869		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		0		5,414
Marketable Securities, Allowance for Credit Loss	0	0		0
Restricted marketable securities		253,236		223,785
Restricted available for sale securities, allowance for credit losses [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss, Beginning Balance	0
Cumulative effect adjustment for the adoption of ASU 2016-13			$ 54
Debt Securities, Available-for-sale, Allowance for Credit Loss, Period Increase (Decrease)	(29)
Debt Securities, Available-for-sale, Allowance for Credit Loss, Securities Sold	(25)
Debt Securities, Available-for-sale, Allowance for Credit Loss, Ending Balance	$ 0
Restricted Debt Securities [Member] \| Minimum [Member]
Restricted available for sale securities, allowance for credit losses [Line Items]
Contractual maturities of Debt securities, Available-for-sale, range start (in years)	10 years
Restricted Debt Securities [Member] \| Maximum [Member]
Restricted available for sale securities, allowance for credit losses [Line Items]
Contractual maturities of Debt securities, Available-for-sale, range end (in years)	21 years
Foreign government obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost				21,991
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax				20
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax				0
Foreign government obligations [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost		128,381		129,499
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		4,502		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		0		3,433
Marketable Securities, Allowance for Credit Loss	$ 0	0
Restricted marketable securities		132,883		126,066
Restricted available for sale securities, allowance for credit losses [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss, Ending Balance	0
US Government Debt Securities [Member] \| Restricted Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Amortized Cost		114,986		99,700
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		5,367		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		0		1,981
Marketable Securities, Allowance for Credit Loss	0	0
Restricted marketable securities		$ 120,353		$ 97,719
Restricted available for sale securities, allowance for credit losses [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss, Ending Balance	$ 0