Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Available-for-sale (AFS) debt securities, at amortized cost	$ 5,470,523	$ 3,320,648
Available-for-sale debt securities pledged as collateral at fair value	588,484	479,432
Allowance for loan losses	619,983	358,287
Loans held-for-investment pledged as collateral	23,263,517	22,431,092
Premises and equipment, accumulated depreciation	$ 127,884	$ 116,790
STOCKHOLDERS’ EQUITY
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	167,240,600	166,621,959
Treasury stock, shares (in shares)	25,675,371	20,996,574

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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