Notes Payable and Revolving Lines of Credit - Schedule of Maturities of Notes Payable (Details) - Notes Payable - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
2019	$ 208,742
2020	699,522
2021	228,015
2022	294,948
2023	915,646
Thereafter	1,820,276
Total	$ 4,167,149	$ 3,763,474

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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