Long-Term Debt - Additional Information (Details)	3 Months Ended	6 Months Ended
	Sep. 30, 2017 USD ($)	Mar. 31, 2018 USD ($)	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018 GBP (£)	Nov. 02, 2017 USD ($)
Debt Instrument [Line Items]
Deferred financing costs	$ 11,724,000	$ 10,854,000
Principal Amount	875,562,000	891,562,000
Carrying amount	863,838,000	880,708,000
Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Deferred financing costs		1,900,000
Term loan A facility
Debt Instrument [Line Items]
Principal amount		$ 400,000,000.0
Quarterly payments of debt	10,000,000
Debt instrument, quarterly periodic payment principal percentage, year one (as a percent)		1.25%														1.25%
Interest rate at end of period (as a percent)		4.65%														4.65%
Term loan A facility | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Deferred financing costs		$ 1,300,000
Term loan A facility | Maximum | Eurocurrency
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		3.00%
Term loan A facility | Maximum | Alternate base rate
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		2.00%
Term loan A facility | Minimum | Eurocurrency
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		2.00%
Term loan A facility | Minimum | Alternate base rate
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		1.00%
Term loan B facility
Debt Instrument [Line Items]
Principal amount		$ 525,000,000.0
Interest rate at end of period (as a percent)		4.20%														4.20%
Debt instrument, quarterly periodic payment principal percentage (as a percent)		0.25%														0.25%
Term loan B facility | Eurocurrency
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		2.50%
Term loan B facility | Alternate base rate
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		1.50%
Term loan B facility | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Deferred financing costs		$ 600,000
Term loan B facility | Minimum | Eurocurrency
Debt Instrument [Line Items]
Debt instrument, variable interest rate (as a percent)		0.75%
Term loan B facility | Minimum | Alternate base rate
Debt Instrument [Line Items]
Debt instrument, variable interest rate (as a percent)		1.75%
Revolving facility
Debt Instrument [Line Items]
Revolving line of credit		$ 180,000,000
Carrying amount	60,000,000
Line of credit facility, current borrowing capacity		$ 99,000,000.0
Voluntary prepayment of debt	$ 34,000,000
Interest rate at end of period (as a percent)		4.61%														4.61%
Debt instrument, term		90 days
Revolving facility | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio	6.25	6.25														6.25
Covenant terms net, debt to EBITDA ratio, current		4.6500														4.6500
Revolving facility | Maximum | Eurocurrency
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		3.00%
Revolving facility | Maximum | Alternate base rate
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		2.00%
Revolving facility | Minimum | Eurocurrency
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		2.00%
Revolving facility | Minimum | Alternate base rate
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		1.00%
Foreign line of credit | Wesco Aircraft Europe Limited
Debt Instrument [Line Items]
Revolving line of credit		$ 7,000,000														£ 5,000,000.0
Line of credit facility, current borrowing capacity | £																£ 5,000,000.0
Foreign line of credit | Base rate | Wesco Aircraft Europe Limited
Debt Instrument [Line Items]
Applicable margin rate (as a percent)		1.65%
Scenario, forecast | Revolving facility | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio			3.00				4.00			4.75	5.25	5.50	5.75		6.00
Scenario, forecast | Revolving facility | Maximum | Fifth Amendment And Restatement Of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio				4.0	4.0	4.0		4.75	4.75					6
Term loan B facility
Debt Instrument [Line Items]
Deferred financing costs	$ 4,162,000	$ 3,552,000
Principal Amount	440,562,000	440,562,000
Carrying amount	436,400,000	437,010,000
Revolving facility
Debt Instrument [Line Items]
Deferred financing costs	0	0
Principal Amount	55,000,000	81,000,000
Carrying amount	55,000,000	81,000,000
Term loan A facility
Debt Instrument [Line Items]
Deferred financing costs	7,562,000	7,302,000
Principal Amount	380,000,000	370,000,000
Carrying amount	$ 372,438,000	$ 362,698,000
Credit agreement, scenario one | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Excess cash flow percentage																	75.00%
Credit agreement, scenario one | Revolving facility | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Principal amount, Capped Incremental Facility																	$ 0
Credit agreement, scenario two | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Excess cash flow percentage																	50.00%
Credit agreement, scenario two | Maximum | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio																	4.00
Credit agreement, scenario two | Minimum | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio																	3.00
Credit agreement, scenario two | Revolving facility | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Principal amount, Capped Incremental Facility																	$ 75,000,000.0
Credit agreement, scenario two | Revolving facility | Maximum | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio																	4.00
Credit agreement, scenario two | Revolving facility | Minimum | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio																	3.50
Credit agreement, scenario three | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Excess cash flow percentage																	25.00%
Credit agreement, scenario three | Maximum | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio																	3.00
Credit agreement, scenario three | Minimum | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio																	2.50
Credit agreement, scenario three | Revolving facility | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Covenant terms net, debt to EBITDA ratio																	3.50
Principal amount, Capped Incremental Facility																	$ 150,000,000.0
Credit agreement, scenario four | Sixth Amendment and Restatement of Credit Agreement
Debt Instrument [Line Items]
Excess cash flow percentage																	0.00%
Covenant terms net, debt to EBITDA ratio																	2.50