CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Amortized cost	$ 181,785	$ 247,607
Allowance for loan losses	328,974	251,475
Tax expense for accumulated other comprehensive (loss) income	$ 8,666	$ 1,696
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)	449,800,000	443,500,000
Common stock held in treasury (in shares)	14,100,000	11,100,000
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

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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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