Debt and Capital Lease Arrangements (Narrative) (Details) - Silicon Valley Bank - Line of Credit - Revolving Credit Facility - 2011 Loan Agreement	12 Months Ended
Dec. 31, 2016 USD ($)
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 40,000,000.0
Debt instrument, minimum net cash balance before increase in variable rate	$ 1
Line of credit facility, unused capacity, commitment fee percentage	0.15%
Debt instrument, covenant, fixed charge coverage ratio, minimum allowed	1.1
Debt instrument, covenant, fixed charge coverage ratio, calculation period	12 months
Line of credit facility, remaining borrowing capacity	$ 40,000,000
Line of credit	$ 0
Debt instrument, covenant, minimum remaining borrowing capacity threshold, percent	20.00%
Debt Instrument, Maturity Date	Sep. 27, 2018
Prime Rate \| Net Cash Balance Exceeding One Dollar, Maintained
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	0.00%
Prime Rate \| Net Cash Balance Exceeding One Dollar, Not Maintained
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	1.50%
London Interbank Offered Rate (LIBOR) \| Net Cash Balance Exceeding One Dollar, Maintained
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	2.00%

Debt Instrument, Covenant, Fixed Charge Coverage Ratio, Calculation Period

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Debt Instrument, Covenant, Minimum Fixed Charge Coverage Ratio

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- Definition

Debt Instrument, Covenant, Minimum Remaining Borrowing Capacity Threshold, Percent

+ References

No definition available.

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- Definition

Debt Instrument, Minimum Net Cash Balance Before Increase in Variable Rate

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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

No definition available.

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- Definition

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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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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