Non-Covered Loans and Allowance for Non-Covered Loan Losses - TDRs (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016 USD ($) item	Mar. 31, 2015 USD ($) item
AB Note | Minimum | Bank
TDRs, Non-covered loans
Number of loans into which a single loan is reconfigured | item	2
Noncovered
TDRs, Non-covered loans
Total Modifications	$ 1,196	$ 75
Recorded Investment in loans
Number of TDRs granted in preceding twelve months for which payment was at least 30 days past due | item	0	0
Noncovered | Payment Term Extension
TDRs, Non-covered loans
Total Modifications	$ 1,196	$ 75
Noncovered | Secured
TDRs, Non-covered loans
Total Modifications	1,196
Noncovered | Secured | Payment Term Extension
TDRs, Non-covered loans
Total Modifications	$ 1,196
Noncovered | Commercial construction loans and land development
TDRs, Non-covered loans
Total Modifications		75
Noncovered | Commercial construction loans and land development | Payment Term Extension
TDRs, Non-covered loans
Total Modifications		$ 75