Notes Receivable (Activity In The Allowance For Loan Losses) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($)
Notes Receivable [Abstract]
Balance, beginning of year	$ 123,791
Provision for credit losses	8,006
Less: Write-offs of uncollectible receivables	(9,100)
Balance, end of year	$ 122,697