Finance Receivables - Finance Receivables, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable
Financing receivable, gross	$ 7,789,401		$ 7,411,816	$ 7,507,132
Allowance for credit losses	(194,996)	$ (190,872)	(189,885)	(193,930)	$ (190,350)	$ (192,471)
Finance receivables, net	7,594,405		7,221,931	7,313,202
Retail
Accounts, Notes, Loans and Financing Receivable
Financing receivable, gross	6,549,707		6,328,201	6,373,926
Allowance for credit losses	(186,722)	(181,426)	(182,098)	(187,502)	(182,150)	(186,254)
Wholesale
Accounts, Notes, Loans and Financing Receivable
Financing receivable, gross	1,239,694		1,083,615	1,133,206
Allowance for credit losses	$ (8,274)	$ (9,446)	$ (7,787)	$ (6,428)	$ (8,200)	$ (6,217)

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount, before allowance for credit loss, of financing receivable.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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