Disclosures About Fair Value of Financial Instruments - Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Available-for-sale securities	$ 276,021	$ 187,565
Held-to-maturity securities	41,996	50,725
Loans held for sale	384	573
Loans held for investment	3,130,669	1,799,155
Real estate acquired by foreclosure	12,122	4,863
Level 1 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash and short term investments	124,906	68,923
Available-for-sale securities	74,974	27,035
Other securities	20,320	11,365
Loans held for sale	384	573
Total	220,584	107,896
Level 2 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Available-for-sale securities	201,047	160,530
Held-to-maturity securities	41,996	50,725
Total	243,043	211,255
Financial Liabilities:
Deposits	3,100,748	1,849,281
Securities sold under agreements to repurchase	3,073	4,605
Other borrowed funds	221,104	47,561
Subordinated debentures	13,187
Total	3,338,112	1,901,447
Level 3 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Loans held for investment	3,147,615	1,788,454
Real estate acquired by foreclosure	12,122	4,863
Total	3,159,737	1,793,317
Carrying Value [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash and short term investments	124,906	68,923
Available-for-sale securities	276,021	187,565
Held-to-maturity securities	42,130	50,713
Other securities	20,320	11,365
Loans held for sale	384	573
Loans held for investment	3,130,669	1,799,155
Real estate acquired by foreclosure	12,122	4,863
Total	3,606,552	2,123,157
Financial Liabilities:
Deposits	3,100,748	1,845,713
Securities sold under agreements to repurchase	3,073	4,605
Other borrowed funds	223,265	47,586
Subordinated debentures	13,187
Total	3,340,273	1,897,904
Fair Value [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash and short term investments	124,906	68,923
Available-for-sale securities	276,021	187,565
Held-to-maturity securities	41,996	50,725
Other securities	20,320	11,365
Loans held for sale	384	573
Loans held for investment	3,147,615	1,788,454
Real estate acquired by foreclosure	12,122	4,863
Total	3,623,364	2,112,468
Financial Liabilities:
Deposits	3,100,748	1,849,281
Securities sold under agreements to repurchase	3,073	4,605
Other borrowed funds	221,104	47,561
Subordinated debentures	13,187
Total	$ 3,338,112	$ 1,901,447

Fair value portion of subordinated debentures.

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

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-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value portion of investments accounted under the cost method.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 25
-Paragraph 1
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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

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No definition available.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

+ References

No definition available.

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Fair value of investments in debt securities classified as held-to-maturity.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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The face amount of loans that will be sold to other entities.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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