Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets
Securities held to maturity, fair value	$ 1,182,846	$ 1,150,833
Loans held for sale (LHFS) measured at fair value	$ 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)	67,481,992us-gaap_CommonStockSharesIssued	67,372,980us-gaap_CommonStockSharesIssued
Common stock, outstanding (in shares)	67,481,992us-gaap_CommonStockSharesOutstanding	67,372,980us-gaap_CommonStockSharesOutstanding

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

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