Loans Receivable, Net - Analysis of Allowance for Loan Losses (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year				$ 15,721				$ 15,183	$ 15,721	$ 15,183	$ 16,722
Provision charged to operations	$ 506	$ 907	$ 706	$ 1,371	$ 1,415	$ 1,165	$ 1,165	$ 700	3,490	4,445	2,623
Charge-offs									(3,841)	(5,384)	(4,490)
Recoveries									1,207	1,477	328
Balance at end of year	$ 16,577				$ 15,721				$ 16,577	$ 15,721	$ 15,183

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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