Commitments And Contingencies (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Operating leases expiration year	2023
Future minimum lease payments, sublease income	$ 11,800,000
Rent expense	7,100,000	$ 7,600,000	$ 4,700,000
Sublease income	700,000	$ 0	$ 0
Future minimum capital lease payments due	$ 0