Debt - Schedule of Debt (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Debt [Roll Forward]
Total debt, Beginning balance	$ 5,705,725
Debt Issuances, Net	2,667,762
Repayments, Extinguishment and Assumptions, Net	(2,467,568)
Accretion and Amortization, Net	7,146
Total debt, Ending balance	5,913,065
Mortgages [Member]
Debt [Roll Forward]
Outstanding balance, Beginning balance	1,529,057
Net premiums (discount), Beginning balance	6,861
Deferred costs, Beginning balance	(7,784)
Total debt, Beginning balance	1,528,134
Debt Issuances	1,032
Debt Issuances, Deferred costs	(326)
Debt Issuances, Net	706
Repayments, Extinguishment and Assumptions	(196,894)
Repayments, Extinguishment and Assumptions of Debt, Premium	(415)
Repayments, Extinguishment and Assumptions of Debt, Deferred costs	65
Repayments, Extinguishment and Assumptions, Net	(197,244)
Accretion and Amortization	(4,951)
Accretion and Amortization, Deferred costs	2,190
Accretion and Amortization, Net	(2,761)
Outstanding balance, Ending balance	1,333,195
Net premiums (discount), Ending balance	1,495
Deferred costs, Ending balance	(5,855)
Total debt, Ending balance	1,328,835
Corporate Bonds [Member]
Debt [Roll Forward]
Outstanding balance, Beginning balance	2,850,000
Net premiums (discount), Beginning balance	(10,419)
Deferred costs, Beginning balance	(25,842)
Total debt, Beginning balance	2,813,739
Debt Issuances	1,800,000
Debt Issuance, Discount	(18,235)
Debt Issuances, Deferred costs	(16,704)
Debt Issuances, Net	1,765,061
Accretion and Amortization	1,605
Accretion and Amortization, Deferred costs	3,825
Accretion and Amortization, Net	5,430
Outstanding balance, Ending balance	4,650,000
Net premiums (discount), Ending balance	(27,049)
Deferred costs, Ending balance	(38,721)
Total debt, Ending balance	4,584,230
Convertible Debt [Member]
Debt [Roll Forward]
Outstanding balance, Beginning balance	321,802
Net premiums (discount), Beginning balance	(1,855)
Deferred costs, Beginning balance	(1,764)
Total debt, Beginning balance	318,183
Repayments, Extinguishment and Assumptions	(321,802)
Repayments, Extinguishment and Assumptions of Debt, Discount	163
Repayments, Extinguishment and Assumptions of Debt, Deferred costs	155
Repayments, Extinguishment and Assumptions, Net	(321,484)
Accretion and Amortization	1,692
Accretion and Amortization, Deferred costs	1,609
Accretion and Amortization, Net	3,301
Outstanding balance, Ending balance	0
Net premiums (discount), Ending balance	0
Deferred costs, Ending balance	0
Total debt, Ending balance	0
Credit Facility [Member]
Debt [Roll Forward]
Outstanding balance, Beginning balance	1,050,000
Deferred costs, Beginning balance	(4,331)
Total debt, Beginning balance	1,045,669
Debt Issuances	902,000
Debt Issuances, Deferred costs	(5)
Debt Issuances, Net	901,995
Repayments, Extinguishment and Assumptions	(1,952,000)
Repayments, Extinguishment and Assumptions of Debt, Deferred costs	3,160
Repayments, Extinguishment and Assumptions, Net	(1,948,840)
Accretion and Amortization, Deferred costs	1,176
Accretion and Amortization, Net	1,176
Outstanding balance, Ending balance	0
Deferred costs, Ending balance	0
Total debt, Ending balance	$ 0