| **BASIS OF PRESENTATION AND ACCOUNTING POLICIES (Tables)** | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            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| **Accounting Policies [Abstract]**                         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        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| Schedule of Error Corrections and Prior Period Adjustments | The following table reflects a summary of the previously reported amounts on the Company's impaired loans as of March 31, 2015.  Recorded Investment(1) UnpaidPrincipalBalance RelatedSpecificReserves AverageRecordedInvestment  (As Reported)  (in thousands)With no related allowance recorded:        Commercial:        Commercial and industrial $3,931 $5,202 $— $4,979Consumer:        Retail installment contracts and auto loans 151,229 196,458 — 149,788With an allowance recorded:        Commercial and industrial 82,515 95,517 39,103 74,350Consumer:        Retail installment contracts and auto loans 2,677,764 3,002,462 237,745 2,241,385Total:        Commercial $377,112 $458,887 $79,474 $386,127Consumer 3,118,177 3,530,149 279,273 2,676,040Total $3,495,289 $3,989,036 $358,747 $3,062,167(1)Recorded investment includes deferred loan fees, net of deferred origination costs and unamortized purchase premiums, net of discounts as well as purchase accounting adjustments.The following table summarizes the impact of the corrections on the Company's Condensed Consolidated Balance Sheet for the three-month period ended March 31, 2015.  As Reported Corrections  As Restated  (in thousands)ASSETS      Loans held for investment  $78,520,165 $(14,305) $78,505,860Allowance for loan and lease losses  (2,493,240) 192,002 (2,301,238)Net loans held for investment 76,026,925 177,697 76,204,622TOTAL ASSETS $123,248,006 $177,697 $123,425,703LIABILITIES      Deferred tax liabilities, net $1,030,676 $68,303 $1,098,979TOTAL LIABILITIES 100,428,674 68,303 100,496,977STOCKHOLDER'S EQUITY      Retained earnings 3,869,581 64,407 3,933,988TOTAL SHUSA STOCKHOLDER’S EQUITY 18,750,262 64,407 18,814,669Noncontrolling interest 4,069,070 44,987 4,114,057TOTAL STOCKHOLDER’S EQUITY 22,819,332 109,394 22,928,726TOTAL LIABILITIES AND STOCKHOLDER’S EQUITY $123,248,006 $177,697 $123,425,703The following table summarizes the impact of the corrections on the Company's Condensed Consolidated Statement of Operations for the three-month period endedMarch 31, 2015.  As Reported Corrections As Restated  (in thousands)Provision for credit losses $872,184 $172,029 $1,044,213NET INTEREST INCOME AFTER PROVISION FOR CREDIT LOSSES 781,975 (172,029) 609,946Lease income 398,385 (86,075) 312,310TOTAL FEES AND OTHER INCOME 655,840 (86,074) 569,766TOTAL NON-INTEREST INCOME 665,397 (86,074) 579,323Lease expense 321,958 (86,075) 235,883TOTAL GENERAL AND ADMINISTRATIVE EXPENSES 1,049,696 (86,075) 963,621INCOME/(LOSS) BEFORE INCOME TAXES 365,012 (172,028) 192,984Income tax provision/(benefit) 112,973 (72,829) 40,144NET INCOME/(LOSS) INCLUDING NONCONTROLLING INTEREST 252,039 (99,199) 152,840LESS: NET INCOME/(LOSS) ATTRIBUTABLE TO NONCONTROLLING INTEREST 93,450 (41,126) 52,324NET INCOME/(LOSS) ATTRIBUTABLE TO SHUSA $158,589 $(58,073) $100,516NOTE 1. BASIS OF PRESENTATION AND ACCOUNTING POLICIES (continued)The following table reflects a summary of the impact of the ACL correction on the Company's Condensed Consolidated Statement of Stockholder's Equity for the three-month period endedMarch 31, 2015.  Retained Earnings Non-controlling Interest Total Stockholder's Equity Retained Earnings Non-controlling Interest Total Stockholder's Equity Retained Earnings Non-controlling Interest Total Stockholder's Equity  As Reported Corrections As Restated  (in thousands)Balance, Beginning of period $3,714,642 $3,960,809 $22,504,095 $122,480 $86,113 $208,593 $3,837,122 $4,046,922 $22,712,688Comprehensive income attributable to SHUSA 158,589 — 210,079 (58,073) — (58,073) 100,516 — 152,006Net income attributable to NCI — 93,450 93,450 — (41,126) (41,126) — 52,324 52,324Balance, End of period $3,869,581 $4,069,070 $22,819,332 $64,407 $44,987 $109,394 $3,933,988 $4,114,057 $22,928,726The following table summarizes the impact of the corrections on the Company's Condensed Consolidated Statement of Cash Flows for the three-month period endedMarch 31, 2015.  As Reported Corrections As Restated  (in thousands)Cash Flows from Operating Activities      Net income including noncontrolling interest: $252,039 $(99,199) $152,840Provision for credit losses 872,184 172,029 1,044,213Deferred tax expense 467 (72,830) (72,363)TDRs (as restated compared to as reported)The following table reflects a summary of the restated amounts on the Company's performing and non-performing TDRs as of March 31, 2015.   March 31, 2015  (As Restated)  (in thousands)Performing $2,875,546Non-Performing 381,848Total $3,257,394The following table reflects a summary of the previously reported amounts on the Company's performing and non-performing TDRs as of March 31, 2015.   March 31, 2015  (As Reported)  (in thousands)Performing $2,962,052Non-Performing 392,256Total $3,354,308NOTE 1. BASIS OF PRESENTATION AND ACCOUNTING POLICIES (continued)The following table details the restated amounts of activity of the Company's TDRs for the three-month period endedMarch 31, 2015. Number ofContracts Pre-ModificationOutstanding RecordedInvestment(1) Post-ModificationOutstanding RecordedInvestment(2) (As Restated) (dollars in thousands)Commercial: Commercial and industrial81 $10,880 $8,166Consumer:      Retail installment contracts and auto loans  75,489 1,112,626 1,110,365Total80,142 $1,156,958 $1,152,222(1)  Pre-TDR modification outstanding recorded investment amount is the month-end balance prior to the month the modification occurred.(2)  Post-TDR modification outstanding recorded investment amount is the month-end balance for the month that the modification occurred.The following table details the previously reported amounts of activity of the Company's TDRs for the three-month period endedMarch 31, 2015. Number ofContracts Pre-ModificationOutstanding RecordedInvestment(1) Post-ModificationOutstanding RecordedInvestment(2) (As Reported) (dollars in thousands)Commercial: Commercial and industrial99 $11,477 $8,448Consumer:      Retail installment contracts and auto loans  80,560 1,190,272 1,131,418Total85,231 $1,235,487 $1,173,271(1)  Pre-TDR modification outstanding recorded investment amount is the month-end balance prior to the month the modification occurred.(2)  Post-TDR modification outstanding recorded investment amount is the month-end balance for the month that the modification occurred.The following table details the restated amounts of the subsequent default activity of the Company's TDRs for the three-month period endedMarch 31, 2015. Number of Contracts Recorded Investment(1) (As Restated) (dollars in thousands)Commercial:   Commercial and industrial10 $276Consumer:     RIC and auto loans9,693 142,534Total9,782 144,305 (1)  The recorded investment represents the period-end balance at March 31, 2015.NOTE 1. BASIS OF PRESENTATION AND ACCOUNTING POLICIES (continued)The following table details the previously reported amounts of the subsequently defaulted activity of the Company's TDRs for the three-month period endedMarch 31, 2015. Number of Contracts Recorded Investment(1) (As Reported) (dollars in thousands)Commercial:   Commercial and industrial10 $276Consumer:     RIC and auto loans13,355 130,290Total13,444 132,061 (1)  The recorded investment represents the period-end balance at March 31, 2015.Fair ValueThe following table summarizes the impact of the corrections on the Company's carrying value of net loans held for investment as of March 31, 2015. As Reported Corrections As Restated (in thousands)Loans held for investment, net$76,026,925 $177,697 $76,204,622SegmentsThe following table details the restated amounts of the Company's segments for the three-month period endedMarch 31, 2015. SC SC Purchase Price Adjustments Eliminations Total(1) Non-GAAP measures (As Restated) (in thousands)Total non-interest income$321,640 $59,202 $(15,723) $579,323Provision for / (release of) credit losses674,688 322,524 — 1,044,213Total expenses444,988 13,743 (13,676) 996,285Income/(loss) before income taxes361,969 (182,297) (1,960) 192,984 (1)  Column represents the consolidated results of SHUSA including segments not disclosed in this table. Refer to Note 17 of the Condensed Consolidated Financial Statements for the complete segmentation.NOTE 1. BASIS OF PRESENTATION AND ACCOUNTING POLICIES (continued)The following table details the previously reported amounts of the Company's segments for the three-month period endedMarch 31, 2015. SC SC Purchase Price Adjustments Eliminations Total(1) Non-GAAP measures (As Reported) (in thousands)Total non-interest income$422,970 $38,317 $(10,093) $665,397Provision for / (release of) credit losses605,982 219,202 — 872,184Total expenses546,318 (7,142) (8,046) 1,082,360Income/(loss) before income taxes430,675 (78,975) (1,960) 365,012(1)  Column represents the consolidated results of SHUSA including segments not disclosed in this table. Refer to Note 17 of the Condensed Consolidated Financial Statements for the complete segmentation.The activity in the ACL by portfolio segment as restated for the three-month period endedMarch 31, 2015 was as follows: Commercial Consumer Unallocated Total (As Restated) (in thousands)Allowance for loan and lease losses, beginning of period$386,837 $1,330,782 $33,024 $1,750,643Provision for loan and lease losses24,908 986,030 38,275 1,049,213Allowance for loan and lease losses, end of period$398,434 $1,831,505 $71,299 $2,301,238NOTE 1. BASIS OF PRESENTATION AND ACCOUNTING POLICIES (continued)The activity in the ACL by portfolio segment as previously reported for the three-month period endedMarch 31, 2015 was as follows: Commercial Consumer Unallocated Total (As Reported) (in thousands)Allowance for loan and lease losses, beginning of period$396,489 $1,679,304 $33,024 $2,108,817Provision for loan and lease losses25,689 813,220 38,275 877,184Allowance for loan and lease losses, end of period$408,867 $2,013,074 $71,299 $2,493,240Impaired Loans (as restated compared to as reported)The following table reflects a summary of the restated amounts on the Company's impaired loans as of March 31, 2015.  Recorded Investment(1) UnpaidPrincipalBalance RelatedSpecificReserves AverageRecordedInvestment  (As Restated)  (in thousands)With no related allowance recorded:        Commercial:        Commercial and industrial $5,132 $6,433 $— $7,830Consumer:        Retail installment contracts and auto loans 146,136 189,983 — 519,849With an allowance recorded:        Commercial and industrial 81,067 94,042 38,661 81,636Consumer:        Retail installment contracts and auto loans 2,586,190 2,902,397 216,586 1,307,306Total:        Commercial $376,865 $458,643 $79,032 $407,028Consumer 3,021,510 3,423,609 258,114 2,230,337Total $3,398,375 $3,882,252 $337,146 $2,637,365(1)Recorded investment includes deferred loan fees, net of deferred origination costs and unamortized purchase premiums, net of discounts as well as purchase accounting adjustments. |

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No definition available.
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| - Definition
Tabular disclosure of prior period adjustments to previously issued financial statements including (1) the effect of the correction on each financial statement line item and any per-share amounts affected for each prior period presented (2) the cumulative effect of the change on retained earnings or other appropriate components of equity or net assets in the statement of financial position, as of the beginning of the earliest period presented, and (3) the effect of the prior period adjustments (both gross and net of applicable income tax) on the net income of each prior period presented in the entity's annual report for the year in which the adjustments are made.
+ References
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