Loans - Summary of Allowance for Loan Losses by Portfolio Class and Category (Details) - Portfolio loans, net - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016
Allowance for Loan Losses [Roll Forward]
Balance at December 31, 2016	$ 39,148	$ 37,565
Provision (provision reversal) for loan losses	3,623	1,533	$ 2,422
Losses charged off	(6,389)	(171)	(1,236)
Recoveries	291	221	433
Balance at March 31, 2017	36,673	39,148	38,292
Commercial and industrial
Allowance for Loan Losses [Roll Forward]
Balance at December 31, 2016	28,778	26,996
Provision (provision reversal) for loan losses	2,955	1,835	1,126
Losses charged off	(6,035)	(133)	(613)
Recoveries	57	80	205
Balance at March 31, 2017	25,755	28,778	26,473
CRE - owner occupied
Allowance for Loan Losses [Roll Forward]
Balance at December 31, 2016	2,730	2,890
Provision (provision reversal) for loan losses	(354)	(249)	245
Losses charged off	(45)	0	(45)
Recoveries	1	89	6
Balance at March 31, 2017	3,040	2,730	3,246
Commercial Real Estate Investor Owned
Allowance for Loan Losses [Roll Forward]
Balance at December 31, 2016	3,324	3,420
Provision (provision reversal) for loan losses	39	(105)	376
Losses charged off	0	0	0
Recoveries	102	9	12
Balance at March 31, 2017	3,387	3,324	3,775
Construction and land development
Allowance for Loan Losses [Roll Forward]
Balance at December 31, 2016	1,302	1,304
Provision (provision reversal) for loan losses	51	(11)	305
Losses charged off	(5)	0	0
Recoveries	49	9	25
Balance at March 31, 2017	1,295	1,302	1,625
Residential real estate
Allowance for Loan Losses [Roll Forward]
Balance at December 31, 2016	2,036	2,023
Provision (provision reversal) for loan losses	451	(3)	299
Losses charged off	(265)	(9)	(503)
Recoveries	62	25	172
Balance at March 31, 2017	2,284	2,036	2,252
Consumer and other
Allowance for Loan Losses [Roll Forward]
Balance at December 31, 2016	978	932
Provision (provision reversal) for loan losses	(47)	66	71
Losses charged off	(39)	(29)	(75)
Recoveries	20	9	13
Balance at March 31, 2017	$ 912	$ 978	$ 921

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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

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

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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=84173941&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=98514028&loc=d3e3602-108585

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