Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
ASSETS
Available-for-sale securities pledged as collateral	$ 429,823	$ 534,327
Allowance for loan losses	310,041	287,128
Loans held-for-investment pledged as collateral	20,387,387	18,880,598
Premises and equipment, accumulated depreciation	$ 115,919	$ 111,898
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)	165,601,141	165,214,770
Treasury stock, shares (in shares)	20,671,710	20,671,710

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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