Debt (Summary of Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Outstanding principal	$ 2,594,732
Carrying value	2,594,732
Deferred financing costs	(8,491)	$ (2,267)
Total debt	2,607,379	2,423,698
Debt classified as current, net of deferred financing costs	(3,008)	(900,759)
Total long-term debt	2,604,371	1,522,939
Margin Loan Facility
Debt Instrument [Line Items]
Outstanding principal	1,300,000
Carrying value	1,300,000	900,000
Senior notes
Debt Instrument [Line Items]
Outstanding principal	775,000
Carrying value	796,138	803,287
Senior credit facility
Debt Instrument [Line Items]
Outstanding principal	512,666
Carrying value	512,666	715,124
Wells Fargo note payable
Debt Instrument [Line Items]
Outstanding principal	7,066
Carrying value	$ 7,066	$ 7,554

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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