Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Assets
Securities held to maturity, fair value	$ 998,043	$ 1,046,247
Shareholders' Equity
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, authorized (in shares)	250,000,000	250,000,000
Common stock, issued (in shares)	67,775,068	67,746,094
Common stock, outstanding (in shares)	67,775,068	67,746,094

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value of investments in debt securities classified as held-to-maturity.

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