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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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- Definition

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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- Definition

Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

No definition available.

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Shareholders' Equity - Summary of Changes in Shareholders' Equity (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Shareholders Equity [Line Items]
Beginning balance, value				$ 415,091us-gaap_StockholdersEquity				$ 372,749us-gaap_StockholdersEquity	$ 415,091us-gaap_StockholdersEquity	$ 372,749us-gaap_StockholdersEquity	$ 372,169us-gaap_StockholdersEquity
Net earnings	(3,092)us-gaap_NetIncomeLoss	10,235us-gaap_NetIncomeLoss	6,637us-gaap_NetIncomeLoss	9,638us-gaap_NetIncomeLoss	5,045us-gaap_NetIncomeLoss	41,877us-gaap_NetIncomeLoss	12,739us-gaap_NetIncomeLoss	10,350us-gaap_NetIncomeLoss	23,418us-gaap_NetIncomeLoss	70,011us-gaap_NetIncomeLoss	12,447us-gaap_NetIncomeLoss
Dividends									(32,402)us-gaap_Dividends	(28,640)us-gaap_Dividends	(12,606)us-gaap_Dividends
Stock-based compensation, Value									917	971	739
Ending balance, value	407,024us-gaap_StockholdersEquity				415,091us-gaap_StockholdersEquity				407,024us-gaap_StockholdersEquity	415,091us-gaap_StockholdersEquity	372,749us-gaap_StockholdersEquity
Common Stock [Member]
Shareholders Equity [Line Items]
Beginning balance, value				334					334		334
Beginning balance, shares				33,397					33,397		33,394
Stock-based compensation, Shares									20		3
Ending balance, value	334								334		334
Ending balance, shares	33,417								33,417		33,397
Paid-in-Capital [Member]
Shareholders Equity [Line Items]
Beginning balance, value				462,397				461,426	462,397	461,426	460,687
Stock-based compensation, Value									917	971	739
Ending balance, value	463,314				462,397				463,314	462,397	461,426
Dividends Paid in Excess of Earnings [Member]
Shareholders Equity [Line Items]
Beginning balance, value				(47,640)				(89,011)	(47,640)	(89,011)	(88,852)
Net earnings									23,418	70,011	12,447
Dividends									(32,402)	(28,640)	(12,606)
Ending balance, value	$ (56,624)				$ (47,640)				$ (56,624)	$ (47,640)	$ (89,011)