Debt (Schedule Of Maturities Of Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
2019	$ 58,185
2020	1,218
2021	135,007
2022	171,006
2023	1,006
Thereafter	20,437
Total	$ 386,859
Corporate [Member] \| Convertible Notes [Member] \| 3.25% Convertible Notes Due 2019 [Member]
Debt Instrument, Interest Rate, Stated Percentage	3.25%
Corporate [Member] \| Convertible Notes [Member] \| 4.125% Convertible Notes Due 2022 [Member]
Debt Instrument, Interest Rate, Stated Percentage	4.125%	4.125%	4.125%

Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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