Employee Benefit Plans Projected Benefit Obligation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 83,676,000
Fair value of plan assets at end of year	$ 87,177,000	$ 83,676,000
Other Postretirement Benefit Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of Increase threshold using citigroup average life discount rate table	0.25%
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of year	$ 1,450,000	1,520,000
Interest cost	43,000	61,000	$ 57,000
Benefit payments	(177,000)	(187,000)
Change in assumptions	38,000	39,000
Experience gain	32,000	(17,000)
Projected benefit obligation at end of year	1,322,000	1,450,000	1,520,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	0
Fair value of plan assets at end of year	0	0
Pension Plans
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of year	86,204,000	79,426,000
Interest cost	2,726,000	3,257,000	3,053,000
Benefit payments	(4,104,000)	(4,114,000)
Change in assumptions	7,532,000	8,259,000
Experience gain	(66,000)	(624,000)
Projected benefit obligation at end of year	92,292,000	86,204,000	79,426,000
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	83,676,000	57,825,000
Actual return on plan assets	7,605,000	9,210,000
Fair value of plan assets at end of year	87,177,000	83,676,000	$ 57,825,000
Employer contributions	$ 0	$ 20,755,000