Finance Receivables - Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment	$ 0		$ 0	$ 184
Collectively evaluated for impairment	194,996		189,885	193,746
Total allowance for credit losses	194,996	$ 190,872	189,885	193,930	$ 190,350	$ 192,471
Individually evaluated for impairment	0		0	220
Collectively evaluated for impairment	7,789,401		7,411,816	7,506,912
Total Finance Receivables	7,789,401		7,411,816	7,507,132
Retail
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment	0		0	0
Collectively evaluated for impairment	186,722		182,098	187,502
Total allowance for credit losses	186,722	181,426	182,098	187,502	182,150	186,254
Individually evaluated for impairment	0		0	0
Collectively evaluated for impairment	6,549,707		6,328,201	6,373,926
Total Finance Receivables	6,549,707		6,328,201	6,373,926
Wholesale
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment	0		0	184
Collectively evaluated for impairment	8,274		7,787	6,244
Total allowance for credit losses	8,274	$ 9,446	7,787	6,428	$ 8,200	$ 6,217
Individually evaluated for impairment	0		0	220
Collectively evaluated for impairment	1,239,694		1,083,615	1,132,986
Total Finance Receivables	$ 1,239,694		$ 1,083,615	$ 1,133,206

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

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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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.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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

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