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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- Definition

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

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No definition available.

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Unsecured senior notes payable (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Unsecured senior notes payable		$ 4,300,000
Ownership interest in subsidiary (as a percent)		100.00%
Outstanding Balance		$ 5,498,442
Proceeds from issuance of unsecured senior notes payable		899,321	$ 1,023,262	$ 348,604
4.00% and 4.70% Unsecured Senior Notes Payable
Debt Instrument [Line Items]
Outstanding Balance	$ 900,000
Proceeds from issuance of unsecured senior notes payable	891,400
4.00% unsecured senior note payable
Debt Instrument [Line Items]
Outstanding Balance	$ 450,000	$ 450,000
Maturity date	Jan. 15, 2024	Jan. 15, 2024
Stated interest rate (as a percent)	4.00%	4.00%
4.70% unsecured senior note payable
Debt Instrument [Line Items]
Outstanding Balance	$ 450,000	$ 450,000
Maturity date	Jul. 01, 2030	Jul. 01, 2030
Stated interest rate (as a percent)	4.70%	4.70%