Minimum excess availability needed for 30 consecutive days to be in compliance with covenant.

No definition available.

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- Definition

Debt Instrument, Covenant Compliance, Minimum Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

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- Definition

Minimum line cap percentage needed for 30 consecutive days to be in compliance with covenant.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of excess availability to be in compliance with covenant.

+ References

No definition available.

+ Details

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- Definition

Minimum percent of line cap to be in compliance with covenant.

+ References

No definition available.

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt is required to be redeemed by the issuer under certain changes in control events.

+ References

No definition available.

+ Details

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- Definition

Date the credit facility was amended.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The fee charged for any outstanding letters of credit issued under the revolving line of credit.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Maximum amount of revolving line of credit that can be used for issuance of letters of credit.

+ References

No definition available.

+ Details

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- Definition

Amount of fair value of long-term debt in excess of carrying amount.

+ References

No definition available.

+ Details

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

- 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

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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-Name Accounting Standards Codification
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Period Type:	duration

- 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
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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Balance Type:	na
Period Type:	duration

- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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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

Date the credit facility first became available, in CCYY-MM-DD format.

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-Publisher FASB
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Balance Type:	na
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.

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-Publisher FASB
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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

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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- 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

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Debt (Narrative) (Details) $ in Thousands				12 Months Ended
Debt (Narrative) (Details) $ in Thousands	May 31, 2019 USD ($)	Sep. 15, 2016 USD ($)	Dec. 01, 2015 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Issued amount				$ 350,000
Payments of debt issuance costs				901	$ 0	$ 38
Long-term debt, gross				350,000	350,000
Letters of credit, amount outstanding				56,100
Long-term debt				346,032	345,197
Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Issuance date		Sep. 15, 2016
Issued amount		$ 350,000
Maturity date		Oct. 01, 2024
Interest rate		5.50%
Change in control repurchase percentage		101.00%
Long-term debt, gross				350,000	350,000
Market value in excess of carrying value				14,900
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 425,000		$ 375,000
Maximum letters of credit issuance			$ 100,000
Unused capacity, commitment fee percentage			0.25%
Minimum fixed charge coverage ratio			1.00
Minimum excess availability for 30 consecutive days			$ 37,700
Threshold for line cap percentage			0.10
Minimum line cap percentage for 30 consecutive days			0.10
Long-term debt, gross				0	$ 0
Initial agreement date			Dec. 01, 2015
Amendment date	May 31, 2019
Threshold for excess availability			$ 37,700
Remaining borrowing capacity				$ 362,300
Revolving Credit Agreement [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Outstanding letters of credit fee			0.0075
Revolving Credit Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Outstanding letters of credit fee			0.0125
Revolving Credit Agreement [Member] \| Base Rate Option [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
Revolving Credit Agreement [Member] \| Base Rate Option [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			0.25%
Revolving Credit Agreement [Member] \| Base Rate Option [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			0.50%
Revolving Credit Agreement [Member] \| LIBOR Rate Option [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			1.25%
Revolving Credit Agreement [Member] \| LIBOR Rate Option [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			1.50%
Revolving Credit Agreement [Member] \| Federal Funds Rate [Member] \| Base Rate Option [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			0.50%
BMCEastLLC [Member] \| Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Equity Method Investment, Ownership Percentage		100.00%
Guarantor Subsidiaries [Member] \| Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Equity Method Investment, Ownership Percentage		100.00%