Debt Instrument, Additional Margin Interest Rate

No definition available.

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- Definition

Letter Of Credit

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Additional Maximum Borrowing Capacity Upon Approval

+ References

No definition available.

+ Details

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

- Definition

Period After Request Is Issued For Interest Payable Rate To Be Determined

+ References

No definition available.

+ Details

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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.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: 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

Reference 2: 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- 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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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Long-Term Indebtedness (Details)				12 Months Ended
Long-Term Indebtedness (Details)	Apr. 27, 2016 USD ($)	Mar. 20, 2015 USD ($)	Feb. 24, 2014 USD ($)	Dec. 31, 2017 USD ($)	Feb. 28, 2018 USD ($)	Jan. 31, 2018 USD ($)	Mar. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Mar. 03, 2015 USD ($)
Line of Credit Facility
Long-term indebtedness				$ 49,924,000				$ 49,949,000
Maximum
Line of Credit Facility
Equity Method Investment, Ownership Percentage	65.00%
Line of Credit
Line of Credit Facility
Amount outstanding				0				0
Remaining availability under the facilities				$ 297,600,000
Maximum leverage ratio				2.5
JPMorgan Chase Bank And Wells Fargo Bank \| Line of Credit
Line of Credit Facility
Maximum borrowings under line of credit							$ 100,000,000		$ 100,000,000.0
Letter of credit				$ 2,400,000				$ 2,500,000
Remaining availability under the facilities				$ 197,600,000
JPMorgan Chase Bank And Wells Fargo Bank \| Line of Credit \| Prime Rate
Line of Credit Facility
Interest rate				1.00%
JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank [Member] \| Line of Credit
Line of Credit Facility
Maximum borrowings under line of credit	$ 200,000,000.0
Additional maximum borrowing capacity upon approval	$ 125,000,000.0
Prudential Investment Management Inc \| Line of Credit
Line of Credit Facility
Long-term indebtedness		$ 50,000,000
Weighted average interest rate		3.35%
Remaining availability under the facilities			$ 150,000,000.0
Debt instrument term (in years)		5 years
Period after request is issued, by company, for interest payable rate to be determined by Prudential			5 days
Option One \| JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank [Member] \| Line of Credit \| LIBOR \| Minimum
Line of Credit Facility
Debt additional margin interest rate	0.00%
Option One \| JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank [Member] \| Line of Credit \| LIBOR \| Maximum
Line of Credit Facility
Debt additional margin interest rate	0.625%
Option One \| JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank [Member] \| Line of Credit \| Federal Funds Effective Rate
Line of Credit Facility
Interest rate	0.50%
Option Two \| JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank [Member] \| Line of Credit \| LIBOR \| Maximum
Line of Credit Facility
Interest rate	1.625%
Subsequent Event \| Amended Credit Agreement
Line of Credit Facility
Maximum borrowings under line of credit					$ 325,000,000	$ 200,000,000