Purchase Credit Impaired ("PCI") Loans - Summary of FDIC Loss Share Receivable (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
FDIC Indemnification Asset [Roll Forward]
Balance December 31, 2014	$ 15,866
Cash received from the FDIC for covered assets	(1,725)	$ (6,487)
FDIC reimbursable losses, net	(1,072)
Amortization, net	(484)
Loan impairment	(2,611)
Reductions for payments on covered assets in excess of expected cash flows	(1,355)
Balance at end of period	$ 8,619