Noncovered Loans Receivable (Change in Accretable Yield) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012		May 01, 2014
Noncovered PCI Loans
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at the beginning of the year	$ 7,714,000		$ 7,352,000		$ 14,638,000
Accretion	(4,305,000)		(4,402,000)		(6,238,000)
Disposals and other	(3,263,000)		(318,000)		(2,798,000)
Change in accretable yield	12,426,000	[1]	5,082,000	[1]	1,750,000	[1]
Balance at the end of the year	12,572,000		7,714,000		7,352,000
Noncovered Loans | Washington Banking
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at the beginning of the year							10,200,000
Balance at the end of the year							10,200,000
Contractual cash flows on loans acquired							75,700,000
Expected cash flows on loans acquired							59,100,000
Non-accretable difference							16,600,000
Estimated fair value of loans acquired							48,900,000
Noncovered Loans | Non-PCI Loans | Washington Banking
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Contractual cash flows on loans acquired							1,120,000,000
Expected cash flows on loans acquired							1,060,000,000
Non-accretable difference							53,500,000
Estimated fair value of loans acquired							841,300,000
Credit card loans acquired in the merger							$ 5,800,000

[1] Includes accretable difference at acquisition.