|**OPERATING LEASE ASSETS, NET (Tables)**                                             | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
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|**Leases [Abstract]**                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Schedule of Operating Lease Assets, Net                                              | Operating lease assets, net consisted of the following as ofMarch 31, 2019andDecember 31, 2018:(in thousands)March 31, 2019December 31, 2018Leased vehicles$19,136,180$18,737,338Less: accumulated depreciation(3,529,738)(3,518,025)Depreciated net capitalized cost15,606,44215,219,313Origination fees and other costs69,23266,967Manufacturer subvention payments(1,287,017)(1,307,424)Leased vehicles, net14,388,65713,978,856Commercial equipment vehicles and aircraft, gross136,176130,274Less: accumulated depreciation(34,734)(30,337)Commercial equipment vehicles and aircraft, net101,44299,937Total operating lease assets, net$14,490,099$14,078,793
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|(in thousands)                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Leased vehicles                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Less: accumulated depreciation                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Depreciated net capitalized cost                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Origination fees and other costs                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Manufacturer subvention payments                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Leased vehicles, net                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
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|Commercial equipment vehicles and aircraft, gross                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Less: accumulated depreciation                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Commercial equipment vehicles and aircraft, net                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
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|Total operating lease assets, net                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Schedule of Future Minimum Rental Payments Due to the Company Under Operating Leases | The following summarizes the future minimum rental payments due to the Company as lessor under operating leases as ofMarch 31, 2019(in thousands):2019$1,862,57620201,909,6732021850,623202275,92820236,978Thereafter11,820Total$4,717,598                                                                                                                                                                                                                                                                                                                                                                                                                         
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|2019                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|2020                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|2021                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|2022                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|2023                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Thereafter                                                                           |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Total                                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    

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