(3) Securitization Trust Debt (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2020	Dec. 31, 2019
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Receivables Pledged at end of period	[1]	$ 2,155,163
Initial Principal		5,945,962
Outstanding Principal		2,060,233	$ 2,109,766
Expected finance receivable payments 2020		225,100
Expected finance receivable payments 2021		717,600
Expected finance receivable payments 2022		510,700
Expected finance receivable payments 2023		396,700
Expected finance receivable payments 2024		92,000
Expected finance receivable payments 2025		86,800
Expected finance receivable payments 2026		$ 18,700
CPS 2014-C [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	December 2021
Receivables Pledged at end of period	[1]	$ 0
Initial Principal		273,000
Outstanding Principal		$ 0	19,758
Weighted Average Contractual Interest Rate		0.00%
CPS 2014-D [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	March 2022
Receivables Pledged at end of period	[1]	$ 0
Initial Principal		267,500
Outstanding Principal		$ 0	23,755
Weighted Average Contractual Interest Rate		0.00%
CPS 2015-A [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	June 2022
Receivables Pledged at end of period	[1]	$ 14,892
Initial Principal		245,000
Outstanding Principal		$ 13,337	26,713
Weighted Average Contractual Interest Rate		5.95%
CPS 2015-B [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	September 2022
Receivables Pledged at end of period	[1]	$ 22,065
Initial Principal		250,000
Outstanding Principal		$ 21,661	36,338
Weighted Average Contractual Interest Rate		5.71%
CPS 2015-C [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	December 2022
Receivables Pledged at end of period	[1]	$ 33,602
Initial Principal		300,000
Outstanding Principal		$ 33,634	53,579
Weighted Average Contractual Interest Rate		6.44%
CPS 2016-A [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	March 2023
Receivables Pledged at end of period	[1]	$ 41,934
Initial Principal		329,460
Outstanding Principal		$ 44,498	71,599
Weighted Average Contractual Interest Rate		6.87%
CPS 2016-B [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	June 2023
Receivables Pledged at end of period	[1]	$ 53,268
Initial Principal		332,690
Outstanding Principal		$ 53,973	82,667
Weighted Average Contractual Interest Rate		7.30%
CPS 2016-C [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	September 2023
Receivables Pledged at end of period	[1]	$ 54,865
Initial Principal		318,500
Outstanding Principal		$ 54,750	83,696
Weighted Average Contractual Interest Rate		7.31%
CPS 2016-D [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	April 2024
Receivables Pledged at end of period	[1]	$ 44,381
Initial Principal		206,325
Outstanding Principal		$ 42,622	65,021
Weighted Average Contractual Interest Rate		5.63%
CPS 2017-A [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	April 2024
Receivables Pledged at end of period	[1]	$ 49,404
Initial Principal		206,320
Outstanding Principal		$ 47,265	71,450
Weighted Average Contractual Interest Rate		5.58%
CPS 2017-B [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	December 2023
Receivables Pledged at end of period	[1]	$ 61,113
Initial Principal		225,170
Outstanding Principal		$ 47,090	76,201
Weighted Average Contractual Interest Rate		4.82%
CPS 2017-C [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	September 2024
Receivables Pledged at end of period	[1]	$ 63,388
Initial Principal		224,825
Outstanding Principal		$ 54,006	80,315
Weighted Average Contractual Interest Rate		4.68%
CPS 2017-D [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	June 2024
Receivables Pledged at end of period	[1]	$ 65,532
Initial Principal		196,300
Outstanding Principal		$ 55,937	83,801
Weighted Average Contractual Interest Rate		4.16%
CPS 2018-A [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	March 2025
Receivables Pledged at end of period	[1]	$ 70,923
Initial Principal		190,000
Outstanding Principal		$ 60,777	91,258
Weighted Average Contractual Interest Rate		3.98%
CPS 2018-B [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	December  2024
Receivables Pledged at end of period	[1]	$ 84,265
Initial Principal		201,823
Outstanding Principal		$ 76,306	111,188
Weighted Average Contractual Interest Rate		4.39%
CPS 2018-C [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	September 2025
Receivables Pledged at end of period	[1]	$ 98,583
Initial Principal		230,275
Outstanding Principal		$ 87,227	130,064
Weighted Average Contractual Interest Rate		4.51%
CPS 2018-D [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	June 2025
Receivables Pledged at end of period	[1]	$ 116,839
Initial Principal		233,730
Outstanding Principal		$ 101,011	149,470
Weighted Average Contractual Interest Rate		4.45%
CPS 2019-A [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	March 2026
Receivables Pledged at end of period	[1]	$ 147,942
Initial Principal		254,400
Outstanding Principal		$ 130,663	186,900
Weighted Average Contractual Interest Rate		4.28%
CPS 2019-B [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	June 2026
Receivables Pledged at end of period	[1]	$ 143,956
Initial Principal		228,275
Outstanding Principal		$ 134,066	184,308
Weighted Average Contractual Interest Rate		3.84%
CPS 2019-C [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	September 2026
Receivables Pledged at end of period	[1]	$ 167,813
Initial Principal		243,513
Outstanding Principal		$ 158,699	216,650
Weighted Average Contractual Interest Rate		3.18%
CPS 2019-D [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	December  2026
Receivables Pledged at end of period	[1]	$ 212,273
Initial Principal		274,313
Outstanding Principal		$ 202,755	265,035
Weighted Average Contractual Interest Rate		2.73%
CPS 2020-A [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	March 2027
Receivables Pledged at end of period	[1]	$ 210,936
Initial Principal		260,000
Outstanding Principal		$ 207,905	0
Weighted Average Contractual Interest Rate		2.72%
CPS 2020-B [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2]	June 2027
Receivables Pledged at end of period	[1]	$ 203,947
Initial Principal		202,343
Outstanding Principal		$ 179,851	0
Weighted Average Contractual Interest Rate		2.92%
CPS 2020-C [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Final Scheduled Payment Date	[2],[3]	November 2027
Receivables Pledged at end of period	[1],[3]	$ 193,242
Initial Principal	[3]	252,200
Outstanding Principal	[3]	$ 252,200	$ 0
Weighted Average Contractual Interest Rate	[3]	1.58%

[1] Includes repossessed assets that are included in Other assets on our Unaudited Condensed Consolidated Balance Sheet.

[2] The Final Scheduled Payment Date represents final legal maturity of the securitization trust debt. Securitization trust debt is expected to become due and to be paid prior to those dates, based on amortization of the finance receivables pledged to the trusts. Expected payments, which will depend on the performance of such receivables, as to which there can be no assurance, are $225.1 million in 2020, $717.6 million in 2021, $510.7 million in 2022, $396.7 million in 2023, $92.0 million in 2024, $86.8 million in 2025, and $18.7 million in 2026.

[3] An additional $63.7 million of receivables were pledged to CPS 2020-C in October 2020.