Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Available for sale debt investment securities Pledged as Collateral, at Fair Value	$ 493,693	$ 435,833
ASSETS
Allowance for loan losses	330,625	311,322
Loans held-for-investment pledged as collateral	21,056,804	20,590,035
Premises and equipment, accumulated depreciation	$ 125,887	$ 118,547
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)	166,532,188	165,867,587
Treasury stock, shares (in shares)	20,985,619	20,906,224

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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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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