Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Restricted Cash and Cash Equivalents Items [Line Items]
Common stock, par value (in usd per share)	$ 0	$ 0
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	220,457,208	220,255,039
Common stock, shares outstanding (in shares)	220,457,208	220,255,039
Cash And Due From Banks
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 55,649	$ 37,408
Interest-bearing Deposits [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 2,630	$ 1,232

Face amount per share of no-par value common stock.

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