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Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands			3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 27, 2019	Sep. 17, 2018	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2012	Dec. 31, 2018
Loss Contingencies [Line Items]
Operating lease rent expense			$ 1,100		$ 3,500
Visa Inc.
Litigation Matters
Settlement agreement amount						$ 4,000,000
Damages sought amended value		$ 4,100,000
Visa deposit in escrow accounts	$ 300,000
Minimum
Loss Contingencies [Line Items]
Weighted average remaining term (in years)				1 year
Finance lease, initial contract terms (in years)				3 years
Maximum
Loss Contingencies [Line Items]
Weighted average remaining term (in years)				13 years
Finance lease, initial contract terms (in years)				5 years
Total commitments and standby letters of credit | Interest payable and other liabilities
Loss Contingencies [Line Items]
Allowance for off balance sheet commitments				$ 1,100			$ 958

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