Debt Instrument, Covenant, Adjusted EBITDA to Interest Expense Ratio, Maximum

No definition available.

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- Definition

Debt Instrument, Covenant, Indebtedness to Adjusted EBITDA Ratio, Maximum

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Net Leverage Ratio, Minimum

+ References

No definition available.

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- Definition

Debt Instrument, Covenant, Repayment of Debt, Percentage of Excess Cash Flow

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Senior Secured Net Indebtedness to Adjusted EBITDA Ratio, Maximum

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Notes Repurchase Price As Percentage Of Principal Amount In Changes Of Control

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Notes Repurchase Price As Percentage Of Principal Amount When Not Use Asset Sales Proceeds For Specific Purposes

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Percentage Of Stock Of First Tier Foreign Subsidiaries Granted To Lenders

+ References

No definition available.

+ Details

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- Definition

Weighted average interest rate of debt outstanding, net of currency swap contract.

+ References

No definition available.

+ Details

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- Definition

The amount of additional borrowing capacity under a line of credit that is available as of the balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of additional margin spread added to the Federal Funds interest rate on borrowings denominated in U.S. dollars.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of additional margin spread added to the LIBOR one month interest rate on borrowings denominated in U.S. dollars.

+ References

No definition available.

+ Details

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- Definition

The maximum fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

The maximum amount of additional margin spread added to LIBOR one month interest rate on borrowings denominated in U.S. dollars.

+ References

No definition available.

+ Details

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- Definition

The minimum fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

The minimum amount of additional margin spread added to the LIBOR one month interest rate on borrowings denominated in U.S. dollars.

+ References

No definition available.

+ Details

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- Definition

The minimum LIBOR one month interest rate on borrowings denominated in US dollars

+ References

No definition available.

+ Details

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- Definition

The minimum LIBOR one month interest rate on eurocurrency borrowings.

+ References

No definition available.

+ Details

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- Definition

Long-term Debt, Additional Repayments of Principal in Next Twelve Months

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum interest rate spread added to adjusted LIBOR rate based on leverage ratio on Eurocurrency borrowings (in hundreths).

+ References

No definition available.

+ Details

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- Definition

Minimum interest rate spread added to adjusted LIBOR rate based on leverage ratio on Eurocurrency borrowings (in hundreths).

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

+ Details

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Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fee for available but unused credit capacity under the credit facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Period Type:	instant

- 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.

+ Details

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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.

+ References

+ Details

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Balance Type:	credit
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- Definition

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

+ References

+ Details

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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Debt Narrative (Details)	12 Months Ended
Debt Narrative (Details)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Apr. 18, 2017 USD ($)	Apr. 04, 2017 USD ($)
Line of Credit Facility
Weighted average interest rate at end of period	5.07%
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 6,609,000
Letters of Credit Outstanding, Amount	4,670,000
Commitment fees on unused lines of credit	$ 570,000
Debt, Weighted Average Interest Rate, net of Currency Swap Contract	4.24%
JPMorgan, 2017 Credit Agreement
Line of Credit Facility
LineOfCreditFacilityInterestRateMarginSpreadAddedToFederalFundsRateOnUSDollarBorrowings	0.50%
Line Of Credit Facility, Minimum LIBOR one month interest rate on borrowings denominated in US dollars	0.00%
LineOfCreditFacilityInterestRateMarginSpreadAddedtoLIBORRateOnUSDollarBorrowings	1.00%
Line Of Credit Facility, Minimum LIBOR one month interest rate on eurocurrency borrowings	0.00%
JPMorgan Chase Bank, National Association, Amended and Restated Credit Agreement
Line of Credit Facility
Weighted average interest rate at end of period		1.64%
Outstanding Borrowings		$ 25,000,000		$ 45,000,000
Prudential Investment Management, Inc. Private Shelf Agreement
Line of Credit Facility
Maximum borrowing capacity		80,000,000
Outstanding Borrowings		11,143,000
Series A Notes
Line of Credit Facility
Face amount		$ 4,000,000
Interest rate, Stated percentage		4.00%
Debt Instrument Term		7 years
Maturity date range, Start		Mar. 08, 2017
Maturity date range, End		Mar. 08, 2018
Series B Notes
Line of Credit Facility
Face amount		$ 7,143,000
Interest rate, Stated percentage		4.10%
Debt Instrument Term		10 years
Maturity date range, Start		Jun. 28, 2017
Maturity date range, End		Jun. 28, 2021
HSBC Bank (China) Company Limited, Shanghai Branch
Line of Credit Facility
Maximum borrowing capacity		$ 5,000,000
Outstanding Borrowings		$ 0
Line of Credit
Line of Credit Facility
Outstanding Borrowings	$ 60,000,000
Line of Credit \| JPMorgan, 2017 Credit Agreement
Line of Credit Facility
Line of Credit Facility, Current Borrowing Capacity	$ 400,000,000
Percentage of stock of first tier foreign subsidiaries granted to lenders	65.00%
Minimum interest rate spread added to adjusted LIBOR rate based on leverage ratio on Eurocurrency borrowings	1.25%
Maximum interest rate spread added to adjusted LIBOR rate based on leverage ratio on Eurocurrency borrowings	2.25%
Face amount			$ 300,000,000
LineOfCreditFacilityMinimumInterestRateMarginSpreadAddedtoLIBORRateOnUSDollarBorrowings	0.25%
LineOfCreditFacilityMaximumInterestRateMarginSpreadAddedToLIBORRateOnUSDollarBorrowings	1.25%
Debt Instrument, Notes Repurchase Price As Percentage Of Principal Amount In Changes Of Control	101.00%
Debt Instrument, Notes Repurchase Price As Percentage Of Principal Amount When Not Use Asset Sales Proceeds For Specific Purposes	100.00%
Revolving Credit Facility
Line of Credit Facility
Outstanding Borrowings	$ 20,000,000
Line of Credit Facility, Remaining Borrowing Capacity	180,000,000
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	5,000,000
Long-term Debt, Additional Repayments of Principal in Next Twelve Months	25,000,000
Long-term Debt, Current Maturities	30,000,000
Revolving Credit Facility \| JPMorgan, 2017 Credit Agreement
Line of Credit Facility
Line of Credit Facility, Current Borrowing Capacity	200,000,000
Additional borrowing capacity available	$ 150,000,000
Minimum commitment fee percentage	0.175%
Maximum commitment fee percentage	0.35%
Minimum interest rate spread added to adjusted LIBOR rate based on leverage ratio on Eurocurrency borrowings	1.075%
Maximum interest rate spread added to adjusted LIBOR rate based on leverage ratio on Eurocurrency borrowings	1.90%
Debt Instrument, Covenant, Indebtedness to Adjusted EBITDA Ratio, Maximum	4.25
Debt Instrument, Covenant, Adjusted EBITDA to Interest Expense Ratio, Maximum	3.50
Debt Instrument, Covenant, Senior Secured Net Indebtedness to Adjusted EBITDA Ratio, Maximum	3.50
Debt Instrument, Covenant, Net Leverage Ratio, Minimum	3.00
LineOfCreditFacilityMinimumInterestRateMarginSpreadAddedtoLIBORRateOnUSDollarBorrowings	0.075%
LineOfCreditFacilityMaximumInterestRateMarginSpreadAddedToLIBORRateOnUSDollarBorrowings	0.90%
Letter of Credit
Line of Credit Facility
Line of Credit Facility, Remaining Borrowing Capacity	$ 175,330,000
Bonds
Line of Credit Facility
Face amount			$ 300,000,000
Interest rate, Stated percentage	5.625%		5.625%
Minimum \| Revolving Credit Facility \| JPMorgan, 2017 Credit Agreement
Line of Credit Facility
Debt Instrument, Covenant, Repayment of Debt, Percentage of Excess Cash Flow	25.00%
Maximum \| Revolving Credit Facility \| JPMorgan, 2017 Credit Agreement
Line of Credit Facility
Debt Instrument, Covenant, Repayment of Debt, Percentage of Excess Cash Flow	50.00%