Accounting for Certain Loans Acquired in a Purchase - Accretable Yield or Income Expected to be Collected (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning balance	$ 4,441	$ 4,658	$ 5,390	$ 5,552
Additions			145
Accretion	$ (1,490)	$ (2,674)	(4,442)	$ (4,619)
Reclassification from nonaccretable	960	1,739	2,826	2,825
Disposals	(143)	(171)	(151)	(206)
Ending balance	3,768	3,552	$ 3,768	3,552
C Financial
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning balance	$ 133
Additions			$ 145
Accretion	$ (8)		$ (20)
Reclassification from nonaccretable
Disposals
Ending balance	$ 125		$ 125
Community
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning balance	$ 1,818		$ 2,122
Additions
Accretion	$ (139)		$ (671)
Reclassification from nonaccretable	21		249
Disposals	(140)		(140)
Ending balance	1,560		1,560
CFS
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning balance	$ 1,732	$ 3,488	$ 2,400	$ 4,164
Additions
Accretion	$ (1,058)	$ (2,156)	$ (2,977)	$ (3,699)
Reclassification from nonaccretable	704	1,428	1,963	2,330
Disposals	(3)	(136)	(11)	(171)
Ending balance	1,375	2,624	1,375	2,624
SCB
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning balance	758	1,170	868	1,388
Accretion	(285)	(518)	(774)	(920)
Reclassification from nonaccretable	$ 235	311	$ 614	495
Disposals		(35)		(35)
Ending balance	$ 708	$ 928	$ 708	$ 928