Employee Stock Ownership Plan - Employee Stock Ownership Plan (ESOP) Disclosures (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Beginning ESOP shares	168,507,000	175,528,000
Shares committed to be released	(7,021,000)	(7,021,000)
Total unallocated shares	161,486	168,507
Fair value of unallocated shares (based on $9.26 and $10.78 share price as of September 30, 2020 and December 31, 2019, respectively)	$ 1,608	$ 1,817