Acquired and Covered Loans (Details) - Changes in Accretable Yield - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Changes in Accretable Yield [Roll Forward]
Beginning balances		$ 20,658	$ 35,152	$ 28,244	$ 36,792
Additions		0	1,265	0	1,265
Accretion		(2,366)	(3,346)	(9,364)	(10,277)
Other	[1]	336	(5,215)	(252)	76
Ending balance		$ 18,628	$ 27,856	$ 18,628	$ 27,856

[1] Increases represent a rise in the expected future cash flows to be collected over the remaining estimated life of the underlying portfolio while decreases result from the resolution of certain loans occurring earlier than anticipated.