Covered Assets and FDIC Loss-sharing Asset (Analysis of Covered Loans) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans, net	$ 4,645,280		$ 4,444,842
Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	294,872		341,142
Valuation discount on covered loans	32,971		43,297
Allowance for loan losses	19,801	20,129	20,174	26,135	29,489	30,056
Loans, net	242,100		277,671
Commercial Portfolio Segment [Member] | Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	60,287		72,870
Real Estate Portfolio Segment [Member] | Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	190,476		212,521
One-to-Four Family Residential Construction [Domain] | Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	9,444		14,781
Commercial and Multifamily Residential Construction [Domain] | Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,910		6,869
Real Estate Construction Portfolio Segment [Member] | Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	13,354		21,650
Consumer Portfolio Segment [Member] | Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	30,755		34,101
One-to-Four Family Residential [Member] | Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	36,711		41,642
Commercial and Multifamily Residential [Member] | Covered Loans [Member]
Covered Assets And FDIC Loss Sharing Asset [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	$ 153,765		$ 170,879