Amount of allowance for credit loss on accounts receivable.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Threshold period for when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Accounting Policies [Line Items]

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Number Of Consecutive Payments To Remove Loans From Non Accrual Status

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Summary of Significant Accounting Policies - Additional Information (Details)		12 Months Ended
	Jun. 13, 2016 USD ($)	Dec. 31, 2019 USD ($) payment	Jan. 01, 2020 USD ($)
Accounting Policies [Line Items]
Period past due		90 days
Number of consecutive payments for borrower status to be normal, as per consistent repayment record \| payment		6
Topic 326 \| Minimum
Accounting Policies [Line Items]
Allowance for credit loss		$ 30,000,000
Topic 326 \| Minimum \| Subsequent Event
Accounting Policies [Line Items]
Reclassification due to the adoption of ASU			$ 24,000,000
Topic 326 \| Maximum
Accounting Policies [Line Items]
Allowance for credit loss		$ 40,000,000
Topic 326 \| Maximum \| Subsequent Event
Accounting Policies [Line Items]
Reclassification due to the adoption of ASU			$ 32,000,000
Senior unsecured fixed - to - floating rate notes
Accounting Policies [Line Items]
Debt instrument, face amount	$ 100,000,000.0
Interest rate on unsecured debt (as percent)	4.50%
Redemption price, percentage (as percent)	100.00%
Senior unsecured fixed - to - floating rate notes \| LIBOR Rate
Accounting Policies [Line Items]
Variable interest rate (as percent)	3.30%
Computer Equipment
Accounting Policies [Line Items]
Useful life		3 years
Furniture and equipment
Accounting Policies [Line Items]
Useful life		5 years
Building Renovations
Accounting Policies [Line Items]
Useful life		10 years