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Summary of Significant Accounting Policies (Loan Securitization and Other Debt Issuance Costs) (Details)	Dec. 31, 2019
Convertible Senior Note Due 2024
Debt Instrument [Line Items]
Other debt issuance and related cost	6.25%
Senior Note Due 2042
Debt Instrument [Line Items]
Other debt issuance and related cost	8.00%

X

- Definition

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

+ 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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