CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Available-for-sale investments at fair value	$ 211,049	$ 182,325
Loans held for investment	358,325	341,121
Tax expense for accumulated other comprehensive (loss) income	$ (704)	$ (3,436)
Preferred stock, stated value (in dollars per share)	$ 0.20	$ 0.20
Preferred stock shares authorized (in shares)	20,000,000	20,000,000
Common stock par value (in dollars per share)	$ 0.20	$ 0.20
Common stock, shares authorized (in shares)	1,125,000,000	1,125,000,000
Common stock shares issued (in shares)	453,300,000	449,900,000
Common stock held in treasury (in shares)	20,900,000	14,200,000
Series B Preferred Stock
Preferred stock, stated value (in dollars per share)	$ 100	$ 100
Preferred stock shares outstanding (in shares)	4,000,000	4,000,000

Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss) attributable to parent.

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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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