Share-Based Compensation - Summary Of Information Of SERP (Details) - SERP - USD ($) shares in Thousands, $ in Thousands	12 Months Ended			72 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Amount of company match expensed under SERP	$ 538	$ 497	$ 538
Treasury shares issued to fund SERP expense	15	16	19	591
SERP trust account balance at December 31	$ 37,765	$ 35,310	$ 31,415
Unrealized gain (loss) recorded in SERP liability account	$ (62)	$ 1,211	$ 3,005