Loans and Allowance for Loan Losses, Financing Receivables Past Due (Details) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		$ 19,977	$ 18,330
Nonperforming	[1]	29,359	16,705
Current and performing		6,493,899	4,554,992
Total Loans		6,543,235	4,590,027
Currently performing impaired loans		19,000	10,200
30-89 Days Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		18,208	18,007
90 Days or More Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		1,769	323
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		4,798	3,436
Nonperforming	[1]	1,683	1,609
Current and performing		2,222,061	1,779,684
Total Loans		2,228,542	1,784,729
Commercial and Industrial [Member] | 30-89 Days Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		4,798	3,431
Commercial and Industrial [Member] | 90 Days or More Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		0	5
Construction and Land Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		309	421
Nonperforming	[1]	7,607	5,173
Current and performing		739,781	316,872
Total Loans		747,697	322,466
Construction and Land Development [Member] | 30-89 Days Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		309	421
Construction and Land Development [Member] | 90 Days or More Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		0	0
Consumer Real Estate - Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		7,776	2,537
Nonperforming	[1]	9,346	4,458
Current and performing		1,029,395	714,163
Total Loans		1,046,517	721,158
Consumer Real Estate - Mortgage [Member] | 30-89 Days Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		6,380	2,391
Consumer Real Estate - Mortgage [Member] | 90 Days or More Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		1,396	146
Commercial Real Estate Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		0	2,232
Nonperforming	[1]	718	0
Current and performing		1,191,268	777,339
Total Loans		1,191,986	779,571
Commercial Real Estate Other [Member] | 30-89 Days Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		0	2,232
Commercial Real Estate Other [Member] | 90 Days or More Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		0	0
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		0	0
Nonperforming	[1]	5,103	4,313
Current and performing		1,078,394	760,207
Total Loans		1,083,497	764,520
Commercial Real Estate Owner Occupied [Member] | 30-89 Days Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		0	0
Commercial Real Estate Owner Occupied [Member] | 90 Days or More Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		0	0
Consumer and Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		7,094	9,704
Nonperforming	[1]	4,902	1,152
Current and performing		233,000	206,727
Total Loans		244,996	217,583
Consumer and Other [Member] | 30-89 Days Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		6,721	9,532
Consumer and Other [Member] | 90 Days or More Past Due and Performing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total past due and accruing		$ 373	$ 172

[1] Approximately $19.0 million and 10.2 million of nonaccrual loans as of December 31, 2015 and 2014, respectively, are currently performing pursuant to their contractual terms.