Long-Term Debt (Narrative) (Details) $ in Thousands | Oct. 31, 2018USD ($) | Oct. 30, 2018USD ($) | Sep. 30, 2018USD ($) | Sep. 30, 2018USD ($)agreement | Sep. 30, 2017USD ($) | May 01, 2018 | Dec. 31, 2017USD ($) | May 07, 2017USD ($) | Oct. 01, 2016USD ($) | Apr. 13, 2015USD ($) | Sep. 11, 2014USD ($) | Jul. 12, 2014USD ($) |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Proceeds from line of credit | | | | | $ 20,000 | | | | | | | |
Repayment of credit facility | | | | | $ 30,000 | | | | | | | |
Ford Motor Credit Company LLC [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Capital lease agreements term | | | | 48 months | | | | | | | | |
Debt instrument stated interest rate | | | | | | 6.88% | | | | | | |
First American Commercial Bancorp [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Number of capital lease agreements | agreement | | | | 3 | | | | | | | | |
Capital lease agreements term | | | | 48 months | | | | | | | | |
Capital lease agreements amount | | | | | | | | | | $ 400 | $ 1,400 | $ 2,700 |
Meridian Leasing Corporation [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Capital lease agreements term | | | | 25 months | | | | | | | | |
Capital lease agreements amount | | | | | | | | | $ 600 | | | |
Debt instrument stated interest rate | | | | | | | | | 11.10% | | | |
Minimum [Member] | First American Commercial Bancorp [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument stated interest rate | | | 3.00% | 3.00% | | | | | | | | |
Maximum [Member] | First American Commercial Bancorp [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument stated interest rate | | | 3.60% | 3.60% | | | | | | | | |
New Credit Agreement [Member] | Capital One, National Association [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument, maturity date | | | | May 8, 2023 | | | | | | | | |
New Credit Agreement [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | $ 269,600 | | | | | | | | | | | |
Debt issuance costs | 1,100 | | | | | | | | | | | |
Debt instrument total net leverage ratio | | 4.25% | | | | | | | | | | |
New Credit Agreement [Member] | Revolving Credit Loan [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | 250,000 | | | | | | | | | | | |
New Credit Agreement [Member] | Delayed Draw Term Loan [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | $ 19,600 | | | | | | | | | | | |
New Credit Agreement [Member] | Minimum [Member] | Revolving Credit Loan [Member] | Capital One, National Association [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Fee charged on unused portion of revolving credit facility | | | | 0.20% | | | | | | | | |
New Credit Agreement [Member] | Maximum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument total net leverage ratio | 3.75% | | | | | | | | | | | |
New Credit Agreement [Member] | Maximum [Member] | Revolving Credit Loan [Member] | Capital One, National Association [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Fee charged on unused portion of revolving credit facility | | | | 0.35% | | | | | | | | |
New Credit Agreement [Member] | One Month Libor [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | 1.00% | | | | | | | | | | | |
New Credit Agreement [Member] | One Month Libor [Member] | Minimum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | 0.00% | | | | | | | | | | | |
New Credit Agreement [Member] | Federal Funds Rate [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | 0.50% | | | | | | | | | | | |
Credit Agreement [Member] | Capital One, National Association [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument, maturity date | | | | May 8, 2022 | | | | | | | | |
Credit Agreement [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | $ 250,000 | | | | | | | | | | |
Debt issuance costs | | 2,900 | | | | | | | | | | |
Credit Agreement [Member] | Revolving Credit Loan [Member] | Capital One, National Association [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | | $ 88,600 | $ 88,600 | | | $ 105,100 | | | | | |
Credit Agreement [Member] | Revolving Credit Loan [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | 125,000 | | | | | | | | | | |
Credit Agreement [Member] | Term Loan [Member] | Capital One, National Association [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument stated interest rate | | | 4.60% | 4.60% | | | 3.86% | | | | | |
Line of credit outstanding amount | | | $ 103,200 | $ 103,200 | | | $ 44,400 | | | | | |
Credit Agreement [Member] | Term Loan [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | 45,000 | | | | | | | | | | |
Credit Agreement [Member] | Delayed Draw Term Loan [Member] | Capital One, National Association [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Proceeds from line of credit | | | $ 0 | $ 60,400 | | | | | | | | |
Credit Agreement [Member] | Delayed Draw Term Loan [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | $ 80,000 | | | | | | | | | | |
Credit Agreement [Member] | Maximum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum ratio used to determine availability of additional draws | | 4.25% | | | | | | | | | | |
Credit Agreement [Member] | One Month Libor [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | | 1.00% | | | | | | | | | | |
Credit Agreement [Member] | One Month Libor [Member] | Minimum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | | 0.00% | | | | | | | | | | |
Credit Agreement [Member] | Federal Funds Rate [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | | 0.50% | | | | | | | | | | |
Terminated Senior Secured Credit Facility [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument, maturity date | | | | Nov. 10, 2020 | | | | | | | | |
Terminated Senior Secured Credit Facility [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | $ 125,000 | | | | | | | | | | |
Terminated Senior Secured Credit Facility [Member] | Revolving Credit Loan [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | | | | | | | $ 100,000 | | | | |
Terminated Senior Secured Credit Facility [Member] | Delayed Draw Term Loan [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | | | | | | | 25,000 | | | | |
Terminated Senior Secured Credit Facility [Member] | Uncommitted Incremental Term Loan [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | | | | | | | 50,000 | | | | |
Terminated Senior Secured Credit Facility [Member] | Letters of Credit [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Maximum aggregate loan amount available | | | | | | | | $ 35,000 | | | | |
A & R Credit Agreement [Member] | Delayed Draw Term Loan [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument, maturity date | | | | Jan. 31, 2019 | | | | | | | | |
Restriction on Dividends [Member] | New Credit Agreement [Member] | Maximum [Member] | Capital One, National Association [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Aggregate amount of dividends and distributions | | | | $ 7,500 | | | | | | | | |
Based On Applicable Senior Leverage Ratio [Member] | New Credit Agreement [Member] | Minimum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | 0.75% | | | | | | | | | | | |
Based On Applicable Senior Leverage Ratio [Member] | New Credit Agreement [Member] | Maximum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | 1.50% | | | | | | | | | | | |
Based On Applicable Senior Leverage Ratio [Member] | Credit Agreement [Member] | Minimum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | | 1.50% | | | | | | | | | | |
Based On Applicable Senior Leverage Ratio [Member] | Credit Agreement [Member] | Maximum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | | 2.25% | | | | | | | | | | |
Based On Applicable Leverage Ratio [Member] | New Credit Agreement [Member] | Minimum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | 1.75% | | | | | | | | | | | |
Based On Applicable Leverage Ratio [Member] | New Credit Agreement [Member] | Maximum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | 2.50% | | | | | | | | | | | |
Based On Applicable Leverage Ratio [Member] | Credit Agreement [Member] | Minimum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | | 2.50% | | | | | | | | | | |
Based On Applicable Leverage Ratio [Member] | Credit Agreement [Member] | Maximum [Member] | Capital One, National Association [Member] | Subsequent Event [Member] | | | | | | | | | | | | |
Debt Instrument [Line Items] | | | | | | | | | | | | |
Debt instrument variable interest rate margin | | 3.25% | | | | | | | | | | |