Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets
Securities held to maturity, fair value	$ 1,212,505	$ 1,182,846
Loans held for sale (LHFS) measured at fair value	$ 133,754	$ 91,182
Shareholders' Equity
Common stock, par value (in dollars per share)	$ 0us-gaap_CommonStockNoParValue	$ 0us-gaap_CommonStockNoParValue
Common stock, authorized (in shares)	250,000,000us-gaap_CommonStockSharesAuthorized	250,000,000us-gaap_CommonStockSharesAuthorized
Common stock, issued (in shares)	67,556,591us-gaap_CommonStockSharesIssued	67,481,992us-gaap_CommonStockSharesIssued
Common stock, outstanding (in shares)	67,556,591us-gaap_CommonStockSharesOutstanding	67,481,992us-gaap_CommonStockSharesOutstanding

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

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

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Fair value of investments in debt securities classified as held-to-maturity.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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