Maximum exercisable period for stock options.

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- Definition

Share based compensation arrangement by share based payment award number of underlying shares available.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award percentage by which tangible book value must increase.

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award receipt deferral percentage.

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share based payment involuntary termination age.

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No definition available.

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- Definition

Share-based compensation arrangement by share based payment participant vested in annual deferral accounts.

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No definition available.

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- Definition

Share-based compensation arrangement by share based payment second vesting requirement for voting common stock per share.

+ References

No definition available.

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- Definition

Share based compensation arrangements number of trading days for vesting requirement.

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Vesting Requirements

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period Subject to Conditions to become Exercisable

+ References

No definition available.

+ Details

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- Definition

Additional vesting requirement - price at which issuer's shares must trade during vesting period to satisfy performance obligation of stock based compensation award.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The total fair value of shares issued during the period under a deferred compensation arrangement.

+ References

+ Details

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- Definition

Number of shares issued pursuant to the terms of a deferred compensation arrangement.

+ References

+ Details

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

+ Details

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

+ 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

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

+ Details

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

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Share-Based Compensation Plans - Narrative (Detail) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 29, 2012 requirement $ / shares	Dec. 31, 2017 USD ($) year $ / shares shares	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum exercisable period for stock options (years)		10 years
Participant vested in an annual deferral accounts		100.00%
Involuntary termination age (year) \| year		65
Employee stock purchase plan expense \| $		$ 6,100	$ 6,200	$ 4,900
Nonvested awards, compensation cost not yet recognized \| $		$ 19,800
Options granted subject to certain conditions in order for them to become exercisable (shares)		650,000
Vesting requirement share price during vesting period \| $ / shares		$ 40
Trading days of voting common stock for vesting requirement	5 days	10 days
Cash received from exercise of options \| $		$ 2,000
Number of vesting requirements \| requirement	2
Second vesting requirement for voting common stock (usd per share) \| $ / shares	$ 17.18
Director \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Voting common stock issued (shares)		31,962
Voting common stock issued \| $		$ 900
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (years)		5 years
Options expiration date (years)		10 years
Service requirement (years)		5 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of exercisable stock options (shares)		96,963
Number of shares granted (shares)		776,500
Tax benefit from exercise of options \| $		$ 10,200
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (years)		3 years
Number of units vested (shares)		256,078
Number of restricted stock units granted (shares)		218,449
Restricted stock units vesting percentage per year		33.33%
Minimum \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (years)		3 years
Maximum \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (years)		5 years
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fully diluted tangible book value		50.00%
Maximum number of shares that may be issued under 2010 plan (shares)		3,666,667
2004 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares that may be issued under 2014 plan (shares)		2,750,000
Aggregate number of shares of common stock available for grant (shares)		1,621,444
2004 Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units vested (shares)		375,402
Number of restricted stock units granted (shares)		177,205
BRRP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding (shares)		263,517
BRRP \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (years)		5 years
Number of restricted stock units granted (shares)		41,244
BRRP \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Receipt deferral percentage under BRRP plan		25.00%
BRRP \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Receipt deferral percentage under BRRP plan		50.00%
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase plan expense \| $		$ 132	$ 103	$ 80
Purchase price under employee stock purchase plan (percent)		85.00%			85.00%
Purchase price under employee stock purchase plan, discount (percent)		15.00%			15.00%