Premises and Equipment, Net - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
Feb. 09, 2018	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Depreciation and amortization for premises and equipment	$ 3,600	$ 18,200	$ 37,600
Amortization expense for computer software	3,200	15,200	31,000
Unamortized computer software costs		$ 58,800	$ 38,700
Fresh-Start Adjustments [Member]
Property, Plant and Equipment [Line Items]
Increase to computer software	$ 33,739

Amount of expense for amortization of capitalized computer software costs.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Total fresh-start adjustment to property and equipment, net.

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