Summary of Other Loss (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Nonoperating Income Expense [Abstract]
Interest expense	$ (7,335)	$ (7,634)
Interest income	2,361	1,872
Amortization of investment discount	4,332	1,259
Other income	470	18
Other loss	$ (172)	$ (4,485)

Amortization of discounts premiums investments cash equivalent and short term investment.

No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
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+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
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+ Details

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

+ Details

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- References

No definition available.

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- Definition

Amount of income (expense) related to nonoperating activities, classified as other.

+ References

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