Loans and Allowance for Loan Losses - Aggregated analysis of the changes in allowance for loan losses - (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Changes in allowance for loan losses
Balance at beginning of period	$ 43,005	$ 38,992	$ 40,355	$ 37,796
Loans charged-off	(1,793)	(1,789)	(3,479)	(3,805)
Recoveries of loans previously charged off	608	932	1,340	1,786
Net charge-offs	(1,185)	(857)	(2,139)	(2,019)
Provision (benefit)		2,728	6,020	5,263
Benefits attributable to FDIC loss share agreements net				23
Total provision for loan losses charged to operations	2,313	2,728	6,020	5,286
Provision for loan losses recorded through the FDIC loss share receivable				(23)
Reduction due to loan removals	(243)	(172)	(346)	(349)
Balance at end of period	43,890	40,691	43,890	40,691
Non-acquired loans
Changes in allowance for loan losses
Balance at beginning of period	38,449	35,115	36,960	34,090
Loans charged-off	(1,292)	(1,557)	(2,589)	(3,276)
Recoveries of loans previously charged off	536	881	1,205	1,645
Net charge-offs	(756)	(676)	(1,384)	(1,631)
Provision (benefit)		2,500	4,573	4,480
Total provision for loan losses charged to operations	2,456	2,500	4,573	4,480
Balance at end of period	40,149	36,939	40,149	36,939
Acquired non-credit impaired loans
Changes in allowance for loan losses
Loans charged-off	(501)	(232)	(890)	(529)
Recoveries of loans previously charged off	72	51	135	141
Net charge-offs	(429)	(181)	(755)	(388)
Provision (benefit)		181	755	388
Total provision for loan losses charged to operations	429	181	755	388
Acquired credit impaired loans
Changes in allowance for loan losses
Balance at beginning of period	4,556	3,877	3,395	3,706
Provision (benefit)	(572)	47	692	395
Benefits attributable to FDIC loss share agreements net				23
Benefits attributable to FDIC loss share agreements				23
Total provision for loan losses charged to operations	(572)	47	692	418
Provision for loan losses recorded through the FDIC loss share receivable				(23)
Reduction due to loan removals	(243)	(172)	(346)	(349)
Balance at end of period	3,741	3,752	3,741	3,752
Residential real estate \| Acquired credit impaired loans
Changes in allowance for loan losses
Provision (benefit)	(192)	(165)	559	(180)
Benefits attributable to FDIC loss share agreements				23
Total provision for loan losses charged to operations	(192)	(165)	559	(157)
Provision for loan losses recorded through the FDIC loss share receivable				(23)
Reduction due to loan removals	(175)	(106)	(237)	(214)
Commercial owner occupied real estate loan \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off		(59)
Recoveries of loans previously charged off	98	14
Total provision for loan losses charged to operations	(453)	(131)
Commercial owner occupied real estate loan \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Loans charged-off			(10)
Recoveries of loans previously charged off			42	6
Total provision for loan losses charged to operations			(32)	(6)
Consumer real estate \| Acquired credit impaired loans
Changes in allowance for loan losses
Provision (benefit)	(37)	217
Total provision for loan losses charged to operations	(37)	217
Reduction due to loan removals	(4)	(45)
Commercial and industrial \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off	(167)	(20)	(189)	(327)
Recoveries of loans previously charged off	143	55	233	103
Total provision for loan losses charged to operations	43	283	257	519
Commercial and industrial \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Loans charged-off		(4)	(2)	(7)
Recoveries of loans previously charged off	1		2	2
Total provision for loan losses charged to operations	(1)	4		5
Commercial and industrial \| Acquired credit impaired loans
Changes in allowance for loan losses
Provision (benefit)	(51)	(5)	136	40
Total provision for loan losses charged to operations	(51)	(5)	136	40
Reduction due to loan removals	(23)	(7)	(54)	(18)
Other income producing property \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off	(7)	(7)	(7)	(7)
Recoveries of loans previously charged off	5	35	48	39
Total provision for loan losses charged to operations	36	(18)	(204)	(183)
Other income producing property \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Recoveries of loans previously charged off	1		1	1
Total provision for loan losses charged to operations	(1)		(1)	(1)
Consumer \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off	(797)	(859)
Recoveries of loans previously charged off	167	216
Total provision for loan losses charged to operations	719	872
Consumer \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Loans charged-off	(140)	(186)	(214)	(336)
Recoveries of loans previously charged off	7	23	19	22
Total provision for loan losses charged to operations	133	163	195	314
Consumer \| Acquired credit impaired loans
Changes in allowance for loan losses
Provision (benefit)				534
Total provision for loan losses charged to operations				534
Reduction due to loan removals			(10)	(69)
Commercial \| Acquired credit impaired loans
Changes in allowance for loan losses
Provision (benefit)				1
Total provision for loan losses charged to operations				1
Reduction due to loan removals			(1)	(22)
Other loans \| Non-acquired loans
Changes in allowance for loan losses
Total provision for loan losses charged to operations	(136)	291
Construction and land development \| Commercial non-owner occupied real estate \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off	(69)	(159)
Recoveries of loans previously charged off	68	442
Total provision for loan losses charged to operations	1,098	(100)
Construction and land development \| Commercial non-owner occupied real estate \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Recoveries of loans previously charged off	1	1
Total provision for loan losses charged to operations	(1)	(1)
Construction and land development \| Commercial non-owner occupied real estate \| Acquired credit impaired loans
Changes in allowance for loan losses
Reduction due to loan removals	(38)	(3)
Construction and land development \| Commercial \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off			(474)	(159)
Recoveries of loans previously charged off			222	607
Total provision for loan losses charged to operations			1,907	101
Construction and land development \| Commercial \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Recoveries of loans previously charged off			2	2
Total provision for loan losses charged to operations			(2)	(2)
Construction and land development \| Commercial \| Acquired credit impaired loans
Changes in allowance for loan losses
Provision (benefit)			(3)
Total provision for loan losses charged to operations			(3)
Reduction due to loan removals			(44)	(26)
Other commercial non-owner occupied real estate \| Non-acquired loans
Changes in allowance for loan losses
Recoveries of loans previously charged off			48	31
Total provision for loan losses charged to operations			1,136	1,057
Other commercial non-owner occupied real estate \| Commercial non-owner occupied real estate \| Non-acquired loans
Changes in allowance for loan losses
Recoveries of loans previously charged off	7	15
Total provision for loan losses charged to operations	693	718
Other commercial non-owner occupied real estate \| Commercial non-owner occupied real estate \| Acquired credit impaired loans
Changes in allowance for loan losses
Provision (benefit)	(292)
Total provision for loan losses charged to operations	(292)
Reduction due to loan removals	(3)	(11)
Home equity loans \| Consumer real estate \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off	(190)	(324)
Recoveries of loans previously charged off	21	87
Total provision for loan losses charged to operations	(40)	288
Home equity loans \| Consumer real estate \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Loans charged-off	(664)	(42)
Recoveries of loans previously charged off	60	24
Total provision for loan losses charged to operations	604	18
Home equity loans \| Consumer \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off			(224)	(767)
Recoveries of loans previously charged off			95	175
Total provision for loan losses charged to operations			165	811
Home equity loans \| Consumer \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Loans charged-off			(664)	(186)
Recoveries of loans previously charged off			69	108
Total provision for loan losses charged to operations			595	78
Consumer \| Consumer \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off			(1,510)	(1,786)
Recoveries of loans previously charged off			378	571
Total provision for loan losses charged to operations			1,314	1,535
Other Consumer \| Consumer \| Non-acquired loans
Changes in allowance for loan losses
Total provision for loan losses charged to operations			(272)	549
Consumer Owner Occupied Loans \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off				(101)
Recoveries of loans previously charged off			105	21
Total provision for loan losses charged to operations			(588)	(258)
Consumer Owner Occupied Loans \| Consumer real estate \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off	(62)	(129)
Recoveries of loans previously charged off	27	17
Total provision for loan losses charged to operations	496	297
Consumer Owner Occupied Loans \| Consumer real estate \| Acquired non-credit impaired loans
Changes in allowance for loan losses
Recoveries of loans previously charged off	2	3
Total provision for loan losses charged to operations	$ (305)	$ (3)
Consumer Owner Occupied Loans \| Consumer \| Non-acquired loans
Changes in allowance for loan losses
Loans charged-off			(185)	(129)
Recoveries of loans previously charged off			76	98
Total provision for loan losses charged to operations			$ 858	$ 349

Amount represents the benefits adjustment attributable to FDIC loss share agreements.

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Amount of change in the reserve, reduction(increase) for loan impairments as a result of current information and events which result in it being probable that estimated cash flows will be significantly higher than previously expected or because actual cash flows are significantly greater than cash flows previously expected for loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

No definition available.

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- Definition

Provision for loan losses recorded through the FDIC loss share receivable - Amount of reduction in the reserve for loans impairments as a result of current information and events which result in it being probable that estimated cash flows will be significantly higher than previously expected or because actual cash flows are significantly greater than cash flows previously expected for loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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No definition available.

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- Definition

Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities. This amount is net of reduction in bad debt expense attributable to collections of loans and lease receivables which had previously been fully or partially charged off as bad debts.

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No definition available.

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- Definition

The sum of the periodic provision charged to earnings before adjustment for amounts covered under loss sharing agreement.

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No definition available.

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

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The increase (decrease) in the allowance for credit losses related to financing receivables.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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