Business Combinations - Schedule of Purchased Performing Loans and Purchased Impaired Loans Acquired in Transfer - Jefferson Bancshares, Inc. (Details) - Jefferson Bancshares $ in Thousands	May 31, 2014 USD ($)
Business Acquisition [Line Items]
Purchased Performing	$ 299,891
PCI	30,021
Total Loans	329,912
Retail Consumer Loans | One-to-four family
Business Acquisition [Line Items]
Purchased Performing	74,378
PCI	6,066
Total Loans	80,444
Retail Consumer Loans | Home equity lines of credit
Business Acquisition [Line Items]
Purchased Performing	16,857
PCI	18
Total Loans	16,875
Retail Consumer Loans | Construction and land/lots
Business Acquisition [Line Items]
Purchased Performing	7,810
PCI	924
Total Loans	8,734
Retail Consumer Loans | Consumer
Business Acquisition [Line Items]
Purchased Performing	3,690
PCI	2
Total Loans	3,692
Commercial | Commercial real estate
Business Acquisition [Line Items]
Purchased Performing	119,635
PCI	15,649
Total Loans	135,284
Commercial | Construction and development
Business Acquisition [Line Items]
Purchased Performing	24,658
PCI	1,012
Total Loans	25,670
Commercial | Commercial and industrial
Business Acquisition [Line Items]
Purchased Performing	52,863
PCI	6,350
Total Loans	$ 59,213