Repurchase Agreement Borrowings (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	$ 11,424	$ 9,076	[1]
Available unpledged securities	243,000	180,600
Residential mortgage-backed securities - GSE [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	11,424	9,076
Market value of collateral	14,800	16,500
Residential mortgage-backed securities - GSE [Member] | Overnight and Continuous [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	11,424	9,076
Residential mortgage-backed securities - GSE [Member] | 1-90 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	0	0
Residential mortgage-backed securities - GSE [Member] | Over 90 Days [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	$ 0	$ 0

[1] Derived from audited consolidated financial statements