The period when the debt instrument is scheduled to be fully repaid.

No definition available.

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- Definition

The number of outstanding lines of credit.

+ References

No definition available.

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer) and the carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount (premium).

+ References

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-Publisher FASB
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Balance Type:	debit
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

+ Details

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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- Definition

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Unsecured Debt - Summary (Details)	12 Months Ended
Unsecured Debt - Summary (Details)	Dec. 31, 2020 USD ($) line_of_credit	Dec. 31, 2019 USD ($)	Nov. 30, 2016 USD ($)	Oct. 31, 2016 USD ($)
Debt Instrument [Line Items]
Unsecured debt, net	$ 5,607,985,000	$ 4,763,206,000
Lines of credit	0	55,000,000
Total unsecured debt	5,607,985,000	4,818,206,000
Unamortized debt issuance expense	$ 1,800,000	2,600,000
Number of outstanding lines of credit \| line_of_credit	2
Unsecured bonds private placement - fixed rate
Debt Instrument [Line Items]
Unsecured debt, net	$ 199,950,000	199,820,000
Weighted Average Maturity In Years	6 months
Term loan - variable rate
Debt Instrument [Line Items]
Unsecured debt, net	$ 550,000,000.0	$ 350,000,000.0	$ 350,000,000.0	$ 225,000,000.0
Weighted average interest rate	1.70%	2.70%
Weighted Average Maturity In Years	1 year 6 months
Term loan - variable rate \| Carrying Value
Debt Instrument [Line Items]
Unsecured debt, net	$ 549,380,000	$ 349,189,000
Bonds public offering - fixed rate
Debt Instrument [Line Items]
Unsecured debt, net	$ 4,858,655,000	$ 4,214,197,000
Weighted average interest rate	3.40%	3.80%
Weighted Average Maturity In Years	9 years 4 months 24 days
Unsecured Line of Credit
Debt Instrument [Line Items]
Lines of credit	$ 0	$ 55,000,000
Weighted average interest rate	1.00%	2.50%
Unsecured Debt
Debt Instrument [Line Items]
Debt instrument, unamortized premium	$ 10,100,000	$ 12,200,000
Unamortized debt issuance expense	31,900,000	24,500,000
Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	1,240,000,000
Unsecured Line of Credit \| Line of Credit
Debt Instrument [Line Items]
Lines of credit	0	55,000,000.0
Unamortized debt issuance expense	3,700,000	$ 3,800,000
Maximum borrowing capacity	$ 1,200,000,000