Portfolio Loans - Summary of Recorded Investment in Impaired Portfolio Loans by Category (Details) (Non-Covered Loans, USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	$ 14,401	$ 21,630
Restructured	1,340	1,360
Loans over 90 days past due and still accruing interest	0	0
Total Recorded Investment	15,741	22,990	21,567
Commercial & Industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	4,291	6,073
Restructured	0	0
Loans over 90 days past due and still accruing interest	0	0
Total Recorded Investment	4,291	6,073
Commercial - Investor Owned
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	0	4,597
Restructured	581	590
Loans over 90 days past due and still accruing interest	0	0
Total Recorded Investment	581	5,187	7,190
Commercial - Owner Occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	560	519
Restructured	759	770
Loans over 90 days past due and still accruing interest	0	0
Total Recorded Investment	1,319	1,289
Construction and Land Development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	6,854	7,348
Restructured	0	0
Loans over 90 days past due and still accruing interest	0	0
Total Recorded Investment	6,854	7,348
Residential Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	2,696	3,093
Restructured	0	0
Loans over 90 days past due and still accruing interest	0	0
Total Recorded Investment	2,696	3,093
Consumer & Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	0	0
Restructured	0	0
Loans over 90 days past due and still accruing interest	0	0
Total Recorded Investment	$ 0	$ 0