Employee Benefit and Deferred Compensation Plans - (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Pension Benefits
Plan expense for noncontributory benefit pension plan and post-retirement health and life plans
Service cost (return)	$ 0	$ 0	$ 0	$ 0
Interest cost (return)	302	274	608	545
Expected (return) on plan assets	(467)	(510)	(936)	(1,021)
Prior service cost recognized	0	0	0	0
Recognized actuarial loss (gain)	102	83	202	156
Net periodic benefit cost (return)	(63)	(153)	(126)	(320)
Pension Benefits | Heritage Financial Group
Plan expense for noncontributory benefit pension plan and post-retirement health and life plans
Service cost (return)	0	0	0	0
Interest cost (return)	69	0	138	0
Expected (return) on plan assets	(45)	0	(90)	0
Prior service cost recognized	0	0	0	0
Recognized actuarial loss (gain)	0	0	0	0
Net periodic benefit cost (return)	24	0	48	0
Other Benefits
Plan expense for noncontributory benefit pension plan and post-retirement health and life plans
Service cost (return)	4	4	8	8
Interest cost (return)	15	15	29	30
Expected (return) on plan assets	0	0	0	0
Prior service cost recognized	0	0	0	0
Recognized actuarial loss (gain)	17	26	34	46
Net periodic benefit cost (return)	$ 36	$ 45	$ 71	$ 84