Loans (Details 10) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance Contractual Amount Receivable				$ 1,544,470					$ 1,544,470
Ending Balance Contractual Amount Receivable	1,613,496				1,544,470				1,613,496	1,544,470
Additional provision for loan loss Recorded Loan Receivable	475	476	448	425	2,619	705	4,097	3,503	1,824	10,924	12,434
Loans and Debt Securities Acquired With Deteriorated Credit Quality [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance Contractual Amount Receivable				855				2,206	855	2,206	3,482
Principal payments received Contractual Amount Receivable									(108)	(697)	(413)
Loans charged off Contractual Amount Receivable									(41)	(487)	(250)
Additional provision for loan loss Contractual Amount Receivable									(203)	(167)	(613)
Loan accretion recorded Contractual Amount Receivable									0	0	0
Ending Balance Contractual Amount Receivable	503				855				503	855	2,206
Beginning Balance Impairment Discount				343				1,003	343	1,003	1,286
Principal payments received Impairment Discount									0	0	0
Loans charged off Impairment Discount									(41)	(487)	(250)
Additional provision for loan loss Impairment Discount									0	0	0
Loan accretion recorded Impairment Discount									(29)	(173)	(33)
Ending Balance Impairment Discount	273				343				273	343	1,003
Beginning Balance Recorded Loan Receivable				512				1,203	512	1,203	2,196
Principal payments received Recorded Loan Receivable									(108)	(697)	(413)
Loans charged off Recorded Loan Receivable									0	0	0
Additional provision for loan loss Recorded Loan Receivable									(203)	(167)	(613)
Loan accretion recorded Recorded Loan Receivable									29	173	33
Ending Balance Recorded Loan Receivable	$ 230				$ 512				$ 230	$ 512	$ 1,203