Represents the purchase price of the underlying equipment at the end of the capital lease term.

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The term of the capital lease.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Amount of the required periodic payments applied to principal.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Borrowings - Term Debt (Details)				12 Months Ended
Borrowings - Term Debt (Details)	Dec. 21, 2017 USD ($) installment	Dec. 30, 2015 USD ($) installment	Jul. 29, 2013 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Aug. 10, 2012 USD ($)
Term Loan
Term loans				$ 1,967,000	$ 3,104,000
Master Lease Agreement
Interest expense including amortization of debt issuance costs and net settlement payments on interest rate swaps				1,900,000	2,000,000	$ 2,200,000
H-P Loan
Term Loan
Term of Term Loan Agreement		5 years
Term debt		$ 3,600,000
Number of quarterly installments for payable of remaining loan principal \| installment		20
Repayment of principal in quarterly installments		$ 195,000
Schedule of remaining principal payments
2019				554,000
2020				759,000
2021				193,000
Total				1,506,000
Master Lease Agreement
Accrued interest (as a percent)		2.95%
H-P Veritas Loan
Term Loan
Term of Term Loan Agreement	3 years
Term debt	$ 700,000
Number of quarterly installments for payable of remaining loan principal \| installment	3
H-P Veritas Loan \| Principal payable in January 2018
Term Loan
Repayment of principal in quarterly installments				239,996
H-P Veritas Loan \| Principal payable in January 2019
Term Loan
Repayment of principal in quarterly installments				229,994
H-P Veritas Loan \| Principal payable in March 2019
Term Loan
Repayment of principal in quarterly installments				229,994
Master Lease Agreement
Master Lease Agreement
Master lease facility, amount				5,000,000			$ 25,000,000
Obligations under capital lease			$ 21,200,000	$ 0	$ 0
Accrued interest (as a percent)			3.39%
Term of capital lease			48 months	48 months
Ending purchase price of underlying assets			$ 1				$ 1