Income Tax Expense (Recovery) - Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Beginning balance	$ 62,958	$ 40,556
Increases for positions related to the current year	2,947	2,106
Increase for positions taken in prior periods		4,121
Decrease for positions taken in prior periods	13,424
Decrease related to statute limitations	1,480	0
Ending balance	$ 51,001	$ 46,783

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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