Leases (Narrative) (Details) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2021 USD ($)		Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)		Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Number of operating leases not yet commenced		3			3			0
Operating lease rent expense	[1]	$ 1,014		$ 1,019	$ 3,055		$ 2,956
Options to extend reasonably certain of being exercised					1,400
Short-term operating lease liabilities		3,100			3,100
Operating lease right-of-use assets		27,518			27,518			$ 29,521
Operating lease liabilities		$ 29,810	[2]		$ 29,810	[2]		$ 31,717

[1] Included in net occupancy expenses in the Unaudited Consolidated Income Statement.

[2] Includes short-term operating lease liabilities of $3.1 million.