Financing Receivable, Allowance For Credit Loss, Forecast Period

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- Definition

Financing Receivable, Allowance For Credit Loss, Increase (Decrease) For Pandemic Forecast

+ References

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- Definition

Financing Receivable, Allowance For Credit Loss, Quantitative Reserve

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- Definition

Financing Receivable, Allowance for Credit Loss, Quantitative Reserve, Period Increase (Decrease)

+ References

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- Definition

Financing Receivable, Allowance for Credit Loss, Specific Reserve

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- Definition

Financing Receivable, Allowance for Credit Loss, Specific Reserve, Period Increase (Decrease)

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No definition available.

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- Definition

Financing Receivable, Credit Loss, Expense (Reversal), COVID-19 Assessment, Forecast Component

+ References

No definition available.

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- Definition

Amount of allowance for credit loss on financing receivable, classified as current.

+ References

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- Definition

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

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- Definition

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.

+ References

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- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

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- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

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- Definition

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

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Allowance for Credit Losses - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2020	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss		$ 117,612	$ 62,224	$ 62,224	$ 60,996
Charge-offs		106,365	16,189
Total loans		7,108,248	7,074,928	7,074,928
Restructured loans		22,650	32,206
COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
Increase (decrease) change in specific reserve		11,300
Specific reserve		13,500	2,200
Increase (decrease) change in qualitative reserve		14,100
Current conditions		$ 2,300
Forecast period (in years)		2 years
Commercial \| COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
Increase (decrease) change in qualitative reserve		$ 3,200
Commercial \| Special mention, substandard, and doubtful \| COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
Increase (decrease) change in quantitative reserve		281,000
Quantitative reserve		571,000	290,000
Commercial \| Substandard \| COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
Increase (decrease) change in quantitative reserve		162,000
Commercial \| Special mention \| COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
Increase (decrease) change in quantitative reserve		113,000
Commercial \| Doubtful \| COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
Increase (decrease) change in quantitative reserve		11,400
Nonperforming TDRs
Financing Receivable, Allowance for Credit Loss [Line Items]
Restructured loans		29,289	8,912
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss			27,346	27,353
Total loans				(27,353)
S&T Legacy Loans \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss				8,200
Commercial and industrial \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss		16,100	15,681		11,596
Charge-offs		74,282	8,928
Restructured loans		13,716	5,661
Commercial and industrial \| Nonperforming TDRs \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Restructured loans		9,885	695
Commercial and industrial \| Cumulative Effect, Period of Adoption, Adjustment \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss			7,853	9,900
Customer fraud, check kiting
Financing Receivable, Allowance for Credit Loss [Line Items]
Charge-offs	$ 58,700
Customer fraud
Financing Receivable, Allowance for Credit Loss [Line Items]
Charge-offs		8,900
Total loans		14,800
Customer fraud \| Nonperforming TDRs
Financing Receivable, Allowance for Credit Loss [Line Items]
Restructured loans		5,900
Customer fraud, commercial real estate \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans		14,000
Customer fraud, line of credit
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans		800
Commercial real estate \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss		65,656	30,577		$ 33,707
Charge-offs		26,460	3,664
Restructured loans		4,791	25,159
Commercial real estate \| Commercial \| Hotel \| COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
Specific reserve		6,700
Commercial real estate \| Nonperforming TDRs \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Restructured loans		16,654	6,713
Commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss			4,810
CARES Act, Paycheck Protection Program Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Restructured loans		195,600
CARES Act, Paycheck Protection Program Loans \| COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans		465,000
ACL provision, COVID-19 assessment, revised forecast		8,600
CARES Act, Paycheck Protection Program Loans \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans		465,000
Business banking \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss		15,917	0
Charge-offs		2,612
Restructured loans		165
Business banking \| Commercial \| COVID-19
Financing Receivable, Allowance for Credit Loss [Line Items]
ACL provision, COVID-19 assessment		3,000
Business banking \| Nonperforming TDRs \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Restructured loans		$ 430
Business banking \| Cumulative Effect, Period of Adoption, Adjustment \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss			12,898
DNB
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans			$ 909,000
DNB \| Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit loss				$ 9,300