Shareholders Equity - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Stockholders Equity Note [Line Items]
Cash dividends paid per share of Common and Class B common stock	$ 0.40	$ 0.25	$ 0.80	$ 0.50
Shares of non-vested restricted stock granted	20,000	0	203,025	87,543
Common stock issued under employee stock purchase plan, shares	2,181	1,744	4,243	3,926
Common stock issued under employee stock purchase plan, net proceeds	$ 213	$ 140	$ 403	$ 299
Non-cash contribution to 401(k) plan			1,759	1,689
401(k) Plan
Stockholders Equity Note [Line Items]
Non-cash contribution to 401(k) plan, shares			18,309	22,551
Non-cash contribution to 401(k) plan			1,759	1,689
Carrier Enterprise I
Stockholders Equity Note [Line Items]
Controlling interest, ownership percentage	70.00%		70.00%
Noncontrolling interest, ownership percentage	30.00%		30.00%
Carrier Enterprise II
Stockholders Equity Note [Line Items]
Controlling interest, ownership percentage	60.00%		60.00%
Noncontrolling interest, ownership percentage	40.00%		40.00%
Carrier Enterprise III
Stockholders Equity Note [Line Items]
Controlling interest, ownership percentage	60.00%		60.00%
Noncontrolling interest, ownership percentage	40.00%		40.00%
Common Stock
Stockholders Equity Note [Line Items]
Stock options exercised, shares	11,250	2,500	23,500	9,500
Stock options exercised, value	646	39	1,329	377
Common Stock \| Non-Vested (Restricted) Stock
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholding related to share based compensation, shares	21,028		21,028
Shares withheld as payment for tax withholding related to share based compensation, market value	$ 2,125		$ 2,125

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

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Publisher FASB

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-Subparagraph (j)

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

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- Definition

Number of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

+ References

No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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- Definition

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Subparagraph (SX 210.3-04)

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

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- Definition

Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

+ References

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