Debt Instrument Convertible Allocated Amount of Equity Component

No definition available.

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- Definition

Debt Instrument Convertible Equity Component Issuance Cost

+ References

No definition available.

+ Details

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- Definition

Percentage Of Principal Amount Of Convertible Notes Is Equal To Repurchase Price

+ References

No definition available.

+ Details

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- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Conversion Rate
-URI http://asc.fasb.org/extlink&oid=6509012

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instruments must exceed threshold percentage for a specified number of trading days to trigger conversion feature, 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

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ 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=34725769&loc=d3e28878-108400

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+ Details

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ 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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- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

+ Details

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- 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

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-Name Accounting Standards Codification
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ References

+ Details

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ 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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Convertible Notes and Credit Facilities - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions		12 Months Ended
	Dec. 14, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 22, 2014
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.00%
Debt Issuance Cost		$ 4,100,000
Payments of Debt Issuance Costs		3,527,000	$ 0	$ 0
Debt Instrument, Face Amount		$ 128,250,000
Debt Instrument, Convertible, Conversion Ratio		173.9978
Debt Conversion, Converted Instrument, Amount		$ 1,000
Percentage Of Principal Amount Of Convertible Notes Is Equal To Repurchase Price		100.00%
Debt Instrument, Convertible, Conversion Price		$ 5.75
Debt Instrument Convertible Allocated Amount of Equity Component		$ 26,925,000
Unamortized Debt Issuance Expense		3,223,000
Debt Instrument Convertible Equity Component Issuance Cost		863,000
Proceeds from convertible debt		$ 128,250,000	0	$ 0
Stock price greater or equal 130 percent of Note Conversion Price [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Threshold Trading Days		20
Debt Instrument, Convertible, Threshold Consecutive Trading Days		30 days
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger		130.00%
Note price less than 98 percent of stock price times conversion rate [Member]
Debt Instrument [Line Items]
Debt Conversion, Converted Instrument, Amount		$ 1,000
Debt Instrument, Convertible, Threshold Trading Days		5
Debt Instrument, Convertible, Threshold Consecutive Trading Days		5 days
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger		98.00%
Standby letters of credit [Member] \| JPMorgan Chase [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity					$ 10,000,000
Revolving Credit Facility [Member] \| JPMorgan Chase [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity					$ 20,000,000
Borrowings under bank line of credit facility		$ 0	$ 0
Privately Negotiated Transactions [Member]
Debt Instrument [Line Items]
Proceeds from convertible debt		$ 49,900,000
Stock Repurchased and Retired During Period, Shares	11.1