Retirement Plans - Safe Harbor plan - (Details 3)	12 Months Ended
	Dec. 31, 2015
Employees' savings plan
Matching contribution by the company (as a percent)	100.00%
Minimum
Employees' savings plan
Age of employees to be eligible to participate in the defined contribution plan	18 years
Percentage of annual base compensation that participants may elect to contribute	1.00%
Maximum
Employees' savings plan
Percentage of annual base compensation that participants may elect to contribute	50.00%
Percentage of employees salary for which the company contributes a matching contribution	5.00%