Significant Accounting Policies Other Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	$ 106,352	$ 103,701
Property and Equipment, Net	42,200	38,500
Accumulated Depreciation	91,000	79,200
Depreciation expense	12,100	9,900	$ 8,700
Goodwill	9,900	9,900
Low income housing tax credits
Property, Plant and Equipment [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets	$ 42,907	$ 54,037