Loans and Allowance for Loan Losses - Summary of Nonperforming Loan Portfolio (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2017	Dec. 31, 2017
Receivables [Abstract]
Valuation allowances	$ 43,486	$ 43,486	$ 20,851
Interest and Fee Income	608	1,283
Unearned paid-in-kind interest on nonaccrual loans	$ 9,712	$ 9,712	$ 4,609

The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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Period Type:	duration