Summary of Significant Accounting Policies (Details)		12 Months Ended
	Oct. 01, 2015 USD ($)	Dec. 31, 2015 USD ($) item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Summary of Significant Accounting Policies
Number of insurance-related subsidiaries | item		2
Investment Securities
Number of components in which other-than-temporary impairment is segregated | item		2
Non-Accrual Loans
Period of charge off for past due unsecured consumer loans		90 days
Minimum period that past due unsecured loans outstanding may not be placed on nonaccrual status under special circumstances		90 days
Maximum period of non-consumer loans outstanding that is used to evaluate whether loans should be placed on non-accrual status		90 days
Other Real Estate Owned
Other real estate owned		$ 55,850,000	$ 69,872,000
Income Taxes
Percentage of likelihood of realization of recognized tax benefit		50.00%
Liability for unrecognized tax benefits		$ 0	0
Interest expense related to uncertain tax positions		0	0	$ 0
Penalties related to uncertain tax positions		0	$ 0	$ 0
Goodwill and Identified Intangible Assets
Goodwill impairment loss	$ 0
Impairment of identified intangible assets		$ 0
Segments of an Enterprise and Related Information
Number of operating segments | item		1
Number of active operating bank subsidiaries | item		4