Secured and Unsecured Debt Financings (Details 1) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Borrowings from unsecured financings, net of debt issuance costs and discounts	$ 4,137,590	$ 3,932,491
Line of Credit Facility, Remaining Borrowing Capacity	$ 450,000
Notes Payable, Other Payables \| ECA Term Financings
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	3.60%
Notes Payable, Other Payables \| Bank Financings
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	3.21%
Senior Notes \| Senior Notes Due 2024
Debt Instrument [Line Items]
Interest rate	4.125%
Borrowings from unsecured financings, net of debt issuance costs and discounts	$ 500,000	500,000
Senior Notes \| Senior Notes Due 2020
Debt Instrument [Line Items]
Interest rate	7.625%
Borrowings from unsecured financings, net of debt issuance costs and discounts	$ 0	300,000
Senior Notes \| Senior Notes due 2021
Debt Instrument [Line Items]
Interest rate	5.125%
Borrowings from unsecured financings, net of debt issuance costs and discounts	$ 500,000	500,000
Senior Notes \| Senior Notes due 2022
Debt Instrument [Line Items]
Interest rate	5.50%
Borrowings from unsecured financings, net of debt issuance costs and discounts	$ 500,000	500,000
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Borrowings from unsecured financings, net of debt issuance costs and discounts		150,000
Line of Credit \| 2013 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Fair Value of Amount Outstanding	$ 650,000
Maximum \| Notes Payable, Other Payables \| ECA Term Financings
Debt Instrument [Line Items]
Interest rate	3.96%
Maximum \| Notes Payable to Banks \| Bank Financings
Debt Instrument [Line Items]
Interest rate	4.55%
Maximum \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Interest rate	1.5709%
4.40% \| Senior Notes \| Senior Notes Due 2023
Debt Instrument [Line Items]
Interest rate	4.40%
Borrowings from unsecured financings, net of debt issuance costs and discounts	$ 650,000	$ 650,000

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

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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

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ 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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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