Long-Term Debt, Transfer

No definition available.

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Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

+ Details

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Balance Type:	debit
Period Type:	duration

- 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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- 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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Balance Type:	na
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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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Balance Type:	debit
Period Type:	duration

- 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Period Type:	instant

- 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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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Debt and Credit Agreements - Narrative (Details) - USD ($)			12 Months Ended
	Nov. 15, 2019	Jan. 05, 2016	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 26, 2017
Debt Instrument [Line Items]
Debt issuance costs incurred and capitalized			$ 2,321,000	$ 0	$ 2,106,000
Amortization of debt issuance costs			2,204,000	2,292,000	1,590,000
Interest expense			3,600,000	7,500,000	6,300,000
Outstanding balance			$ 50,000,000	140,000,000
Wells Fargo Bank
Debt Instrument [Line Items]
Debt issuance costs incurred and capitalized					$ 2,100,000
Revolving Credit Facility
Debt Instrument [Line Items]
Term of debt instrument			5 years
Letter of Credit \| Wells Fargo Bank
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 10,000,000.0
Swing Line Loan \| Wells Fargo Bank
Debt Instrument [Line Items]
Maximum borrowing capacity		10,000,000.0
Line of Credit
Debt Instrument [Line Items]
Debt issuance costs incurred and capitalized			$ 2,300,000
Line of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank \| Minimum
Debt Instrument [Line Items]
Commitment fee rate on undrawn commitments	0.15%
Line of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank \| Maximum
Debt Instrument [Line Items]
Commitment fee rate on undrawn commitments	0.30%
Line of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank \| LIBOR
Debt Instrument [Line Items]
Spread on variable interest rate	1.00%
Line of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank \| LIBOR \| Minimum
Debt Instrument [Line Items]
Spread on variable interest rate	1.25%
Line of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank \| LIBOR \| Maximum
Debt Instrument [Line Items]
Spread on variable interest rate	2.00%
Line of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank \| Federal Funds
Debt Instrument [Line Items]
Spread on variable interest rate	0.50%
Line of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank \| LIBOR Plus 1.00% \| Minimum
Debt Instrument [Line Items]
Spread on variable interest rate	0.25%
Line of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank \| LIBOR Plus 1.00% \| Maximum
Debt Instrument [Line Items]
Spread on variable interest rate	1.00%
Line of Credit \| Secured Credit Facility \| Wells Fargo Bank
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 400,000,000.0
Line of Credit \| Secured Credit Facility \| Wells Fargo Bank \| LIBOR \| Interest Rate Option One \| Minimum
Debt Instrument [Line Items]
Spread on variable interest rate		1.50%
Line of Credit \| Secured Credit Facility \| Wells Fargo Bank \| LIBOR \| Interest Rate Option One \| Maximum
Debt Instrument [Line Items]
Spread on variable interest rate		2.25%
Line of Credit \| Secured Credit Facility \| Wells Fargo Bank \| LIBOR \| Interest Rate Option Two \| Minimum
Debt Instrument [Line Items]
Spread on variable interest rate		0.50%
Line of Credit \| Secured Credit Facility \| Wells Fargo Bank \| LIBOR \| Interest Rate Option Two \| Maximum
Debt Instrument [Line Items]
Spread on variable interest rate		1.25%
Line of Credit \| Secured Credit Facility \| Wells Fargo Bank \| Federal Funds \| Interest Rate Option Two
Debt Instrument [Line Items]
Spread on variable interest rate		0.50%
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Balance transfer	$ 80,000,000.0		80,000,000
Outstanding balance			50,000,000	0
Line of Credit \| Revolving Credit Facility \| Wells Fargo Bank
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 200,000,000.0				$ 315,000,000.0
Term of debt instrument		5 years
Line of Credit \| Revolving Credit Facility \| Wells Fargo Bank \| Minimum
Debt Instrument [Line Items]
Commitment fee rate on undrawn commitments		0.20%
Line of Credit \| Revolving Credit Facility \| Wells Fargo Bank \| Maximum
Debt Instrument [Line Items]
Commitment fee rate on undrawn commitments		0.35%
Line of Credit \| Revolving Credit Facility \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000,000.0
Term of debt instrument	5 years
Line of Credit \| Term Loan Facility
Debt Instrument [Line Items]
Balance transfer	$ (80,000,000.0)		(80,000,000)
Outstanding balance			$ 0	$ 140,000,000
Line of Credit \| Term Loan Facility \| Wells Fargo Bank
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 200,000,000.0
Term of debt instrument		5 years
Line of Credit \| Letter of Credit \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank
Debt Instrument [Line Items]
Maximum borrowing capacity	15,000,000.0
Line of Credit \| Swing Line Loan \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank
Debt Instrument [Line Items]
Maximum borrowing capacity	25,000,000.0
Line of Credit \| Incremental Loan Facility \| Wells Fargo Securities, Citizens Bank and JP Morgan Chase Bank
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 250,000,000.0