Face (par) amount of debt instrument at time of issuance.

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Balance Type:	na
Period Type:	duration

- Definition

Date the debt instrument was offered for sale, in CCYY-MM-DD format.

+ References

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- Definition

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.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

issuance cost on senior notes that will be amortized to interest expense over the 10 year term

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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Debt And Interest Expense Debt and Interest Expense (Senior Notes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	May 01, 2018
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 12, 2024
Debt Instrument, Face Amount			$ 1,250,000
issuance cost on senior note	$ (12,435)	$ (14,953)
Senior Notes	$ 1,787,565	1,785,047
Due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Offering Date	Apr. 16, 2013
Debt Instrument, Maturity Date	May 01, 2023
Debt Instrument, Interest Rate, Stated Percentage	4.625%
Debt Instrument, Face Amount	$ 750,000	750,000
Due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Offering Date	Mar. 27, 2015
Debt Instrument, Maturity Date	Apr. 01, 2025
Debt Instrument, Interest Rate, Stated Percentage	5.25%
Debt Instrument, Face Amount	$ 500,000	500,000
Due 2027
Debt Instrument [Line Items]
Debt Instrument, Offering Date	Jul. 05, 2017
Debt Instrument, Maturity Date	Jul. 15, 2027
Debt Instrument, Interest Rate, Stated Percentage	4.75%
Debt Instrument, Face Amount	$ 550,000	$ 550,000