Loans Held for Investment - Purchased Credit Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Loans Held for Investment
Total purchase credit impaired	$ 4,371	$ 4,559
Commercial and industrial
Loans Held for Investment
Total purchase credit impaired	2,536	2,586
Commercial owner occupied
Loans Held for Investment
Total purchase credit impaired	481	491
Commercial non-owner occupied
Loans Held for Investment
Total purchase credit impaired	1,036	1,088
One-to-four family
Loans Held for Investment
Total purchase credit impaired	0	1
Other loans
Loans Held for Investment
Total purchase credit impaired	$ 318	$ 393

The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to commercial loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant