Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Unrealized holding gains arising during the period net of tax effects	$ 6,681	$ 2,461	$ 5,843	$ 8,955
Reclassification adjustment for gains included in net income net of tax effects	98	204	549	213
Change in fair value of derivative instruments designated as cash flow hedges net of tax effects	$ 1,837	$ 0	$ 201	$ 0