Debt instrument convertible conversion price denomination value.

No definition available.

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- Definition

Senior notes pricing.

+ References

No definition available.

+ Details

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- Definition

Minimum required percentage of holders to declare repurchase of notes.

+ References

No definition available.

+ Details

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- Definition

Percentage of notes to repurchased on declaration by minimum required holders.

+ References

No definition available.

+ Details

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

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Period Type:	duration

- Definition

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

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- Definition

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

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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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

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

+ References

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Amount, after accumulated amortization, of debt discount.

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- Definition

The after-tax amount of interest recognized in the period associated with any convertible debt.

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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.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Long-Term Borrowings - Additional Information (Detail) - USD ($)			3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 17, 2017	Jul. 18, 2013	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Debt Instrument [Line Items]
Repurchase of common stock, shares						1,795,444
Repurchase of common stock					$ 199,000	$ 11,401,000
Debt issuance costs paid						5,902,000
Interest expense related to the Exchangeable Notes						2,542,000
6.625% Senior Notes Due 2021 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount		$ 225,000,000
Interest rate		6.625%	6.625%		6.625%		6.625%
Due date		Jul. 15, 2021			Jul. 15, 2021		Jul. 15, 2021
Aggregate principal amount of senior notes pricing		99.50%
Debt issuance costs paid		$ 5,039,000
Interest expense related to the Exchangeable Notes			$ 3,926,000	$ 3,914,000	$ 7,852,000	7,826,000
Original debt issue discount		$ 1,125,000
6.625% Senior Notes Due 2021 [Member] \| Senior Notes [Member] \| 2017 [Member]
Debt Instrument [Line Items]
Redemption price plus accrued, unpaid interest and special interest to the date of redemption					101.656%
6.625% Senior Notes Due 2021 [Member] \| Senior Notes [Member] \| 2018 [Member]
Debt Instrument [Line Items]
Redemption price plus accrued, unpaid interest and special interest to the date of redemption					100.00%
5.0% Exchangeable Senior Notes due March 2021 [Member] \| Exchangeable Senior Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount	$ 86,250,000
Interest rate	5.00%		5.00%		5.00%		5.00%
Due date	Mar. 01, 2021				Mar. 01, 2021		Mar. 01, 2021
Aggregate principal amount of senior notes pricing	5.00%
Convertible notes principal amount denomination value					$ 1,000
Conversion of converted notes, shares issued					121.1387
Exchange price			$ 8.26		$ 8.26
Redemption price plus accrued, unpaid interest and special interest to the date of redemption					100.00%
Minimum required percentage of holders to declare repurchase of notes					25.00%
Percentage of notes to repurchased on declaration by minimum required holders					100.00%
Debt issuance costs paid	$ 5,902,000				$ 5,902,000
Interest expense related to the Exchangeable Notes			$ 1,418,000	$ 1,395,000	$ 2,829,000	$ 2,542,000