Loans and Leases (Accretable Yield Movement Schedule) (Details) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, beginning of period	$ 127,624	$ 184,158
Additions	110,757	0
Accretion to interest income	(62,147)	(51,790)
Disposals	(32,466)	(19,958)
Reclassifications from nonaccretable difference	57,931	15,214
Balance, end of period	201,699	127,624
Evergreen Bank [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, beginning of period	20,063	34,567
Additions	0	0
Accretion to interest income	(11,340)	(12,695)
Disposals	(5,457)	(3,221)
Reclassifications from nonaccretable difference	6,200	1,412
Balance, end of period	9,466	20,063
Rainer [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, beginning of period	71,789	102,468
Additions	0	0
Accretion to interest income	(18,264)	(23,511)
Disposals	(11,217)	(12,362)
Reclassifications from nonaccretable difference	7,681	5,194
Balance, end of period	49,989	71,789
Nevada Security Bank [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, beginning of period	34,632	46,353
Additions	0	0
Accretion to interest income	(13,791)	(15,292)
Disposals	(5,841)	(3,703)
Reclassifications from nonaccretable difference	8,666	7,274
Balance, end of period	23,666	34,632
Circle Bancorp [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, beginning of period	1,140	770
Additions	0	0
Accretion to interest income	(344)	(292)
Disposals	0	(672)
Reclassifications from nonaccretable difference	0	1,334
Balance, end of period	796	1,140
Sterling Financial Corporation [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, beginning of period	0
Additions	110,757
Accretion to interest income	(18,408)
Disposals	(9,951)
Reclassifications from nonaccretable difference	35,384
Balance, end of period	$ 117,782

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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Amount of decrease from accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of additions to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of reduction, resulting from a sale or transfer of a loan, in the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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