Purchased Loans (Details Textual)	12 Months Ended
	Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan	Dec. 31, 2014 USD ($)
Loans and Allowance for Loan Losses (Textual) [Abstract]
Restructured loans discontinued past due period	90 days
Allowance for loan losses attributable to restructured loans	$ 42,737,000	$ 42,437,000
Purchased
Loans and Allowance for Loan Losses (Textual) [Abstract]
Nonperforming loans charged off past due period	90 days
Number of restructured loans | loan	3	1
Restructured loans discontinued past due period	90 days	90 days
Average recorded investment in impaired loans	$ 6,594,000	$ 2,860,000	$ 2,037,000
Interest income recognized on impaired loans			$ 59,000
Remaining availability under commitments to lend additional funds on restructured loans	3,000	0
Fair value of loans contractual principal cash flows amount	81,673,000	83,078,000
Fair value of loans contractual interest cash flows	41,000	241,000
Fair value of loans contractual interest payments	1,776,000	2,312,000
Fair value of loans contractual purchase discount	34,550,000	45,980,000
Purchased | Nonaccruing Loans
Loans and Allowance for Loan Losses (Textual) [Abstract]
Outstanding balance of restructured loans	0	275,000
Purchased | Restructured Loans
Loans and Allowance for Loan Losses (Textual) [Abstract]
Outstanding balance of restructured loans	1,206,000	4,778,000
Allowance for loan losses attributable to restructured loans	$ 35,000	$ 95,000