Leases Leases (Supplemental Cash Flow and Balance Sheet Information) (Details) - USD ($)		12 Months Ended
	Jan. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases		$ 1,434,000	$ 1,394,000
Operating cash flows from finance leases		151,000	68,000
Financing cash flows from finance leases		142,000	106,000	$ 0
Right-of-use assets obtained in exchange for new lease obligations:
Operating leases		2,002,000	14,030,000
Finance leases		$ 3,668,000	$ 1,612,000
Weighted average remaining lease term (years)
Operating leases		15 years 4 months 24 days	15 years 2 months 12 days
Finance leases		27 years	22 years 4 months 24 days
Weighted average discount rate:
Operating Leases		3.40%	3.39%
Finance leases		3.44%	4.00%
ASU 2016-02
Right-of-use assets obtained in exchange for new lease obligations:
Operating leases	$ 10,500,000
Finance leases	$ 1,600,000