Employee Benefits - Performance-based Awards (Details) (2010 Option Plan, Employee And Directors Performance Options, USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014
2010 Option Plan | Employee And Directors Performance Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Shares granted	11,958
Total fair value of options granted during period (in dollars)	$ 22
Nonvested options outstanding	1,277,990