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.

No definition available.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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STOCKHOLDERS' EQUITY - Schedule of amounts reclassified from AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Changes in Accumulated Other Comprehensive Income (Loss)
Investment income, net	$ 2,912	$ 7,669	$ 3,009	$ 14,324
Foreign currency adjustment	$ 0	$ 0	25	0
Reclassification Out Of Accumulated Other Comprehensive Income
Changes in Accumulated Other Comprehensive Income (Loss)
Total reclassifications			25	344
Reclassification Out Of Accumulated Other Comprehensive Income \| Unrealized Gain (Loss) on Marketable Securities
Changes in Accumulated Other Comprehensive Income (Loss)
Investment income, net			0	344
Reclassification Out Of Accumulated Other Comprehensive Income \| Foreign Currency Translation Adjustments
Changes in Accumulated Other Comprehensive Income (Loss)
Foreign currency adjustment			$ 25	$ 0