Shares distributed from employee trust during period shares.

No definition available.

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- Definition

Stockholders' equity note.

+ References

No definition available.

+ Details

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

+ References

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- Definition

Number of new stock issued during the period.

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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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Shareholders Equity - Summary of Changes in Shareholders Equity (Parenthetical) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Stockholders Equity Note [Line Items]
Tax provision (benefit) for recognized net actuarial loss (gain)	$ (35)		$ (39)		$ (70)	$ (70)
Unrecognized Pension Benefit Cost [Member]
Stockholders Equity Note [Line Items]
Tax provision (benefit) for recognized net actuarial loss (gain)	$ 35	$ 35	$ 31	$ 31
Treasury Stock [Member]
Stockholders Equity Note [Line Items]
Purchase of common shares	13,800	52,590	29,724	75,246
Common Shares [Member]
Stockholders Equity Note [Line Items]
Issuance of common shares	7,400	63,316	525	77,381
Common Shares Issued to Rabbi Trust [Member]
Stockholders Equity Note [Line Items]
Common shares distributed from rabbi trust	400	3,727	525	3,358
Deferred Compensation Liability [Member]
Stockholders Equity Note [Line Items]
Common shares distributed from rabbi trust	400	3,727	525	3,358
Retained Earnings [Member]
Stockholders Equity Note [Line Items]
Cash dividends declared per share	$ 0.20	$ 0.20	$ 0.20	$ 0.20