Interim Consolidated Financial Statements - Summary of Additional Lease Information (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)
Leases [Abstract]
Cash paid for amounts included in the measurement of operating lease liabilities	$ 7,762
Operating right-of-use assets obtained in exchange for lease obligations	$ 16,626
Weighted-average remaining lease term - operating leases (years)	6 years 8 months 12 days
Weighted-average discount rate - operating leases	5.10%

No definition available.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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-Publisher FASB
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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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