Consolidated Balance Sheet - Unaudited (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
ASSETS
AFS debt securities, amortized cost	$ 9,783,180	$ 5,470,523
Available for sale debt investment securities pledged as collateral, fair value	859,901	588,484
Allowance for loan losses, beginning of period	560,404	619,983
Loans held-for-investment pledged as collateral	24,551,177	23,263,517
Premises and equipment, accumulated depreciation	$ 136,796	$ 127,884
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)	167,764,049	167,240,600
Treasury stock, shares (in shares)	25,880,318	25,675,371

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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