XML 47 R32.htm IDEA: XBRL DOCUMENT v3.8.0.1

Accounting for Stock Based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Option Activity

The following table summarizes stock option activity during the three year period ended December 31, 2017:

Options		Shares				Weighted- Average Exercise Price				Weighted- Average Remaining Contractual Term				Aggregate Intrinsic Value
Outstanding at December 31, 2014			1,674,534			$	19.14
Granted			524,534				41.97
Exercised			(571,723	)			16.21
Forfeited			(96,500	)			28.47
Outstanding at December 31, 2015			1,530,845			$	27.46				4.97			$	30,573
Granted			862,000				40.87
Exercised			(112,875	)			13.24
Forfeited			(176,500	)			39.32
Outstanding at December 31, 2016			2,103,470			$	32.72				4.86			$	12,265
Granted			808,500				37.23
Exercised			(202,328	)			13.62
Forfeited			(57,500	)			42.54
Outstanding at December 31, 2017			2,652,142			$	35.34				4.76			$	6,964
Exercisable at December 31, 2015			439,561			$	12.18				3.51			$	15,480
Exercisable at December 31, 2016			675,152			$	21.40				3.45			$	9,646
Exercisable at December 31, 2017			984,374			$	29.84				3.44			$	6,534

Fair Value of Option on Date of Grant

The fair value of each option is estimated on the date of grant using the Black-Scholes option-pricing model in order to measure the compensation cost associated with the award. This model incorporates certain assumptions for inputs including a risk-free interest rate, expected dividend yield of the underlying Common Stock, expected option life and expected volatility in the market value of the underlying Common Stock. The following assumptions were used for options issued in the following periods:

		2017		2016		2015
Expected volatility		33%		37%		35%
Weighted average expected volatility		33%		37%		35%
Expected lives		3 yrs.		3 yrs.		3 yrs.
Risk-free interest rate		1.49-1.93%		0.90-1.07%		1.00%
Expected dividend yield		none		none		none

Restricted Stock Activity

The following table summarizes restricted stock activity during the three year period ended December 31, 2017:

Unvested Restricted Shares		Shares				Weighted- Average Grant-Date Fair Value
Nonvested at December 31, 2014			177,084			$	23.70
Granted			108,026				44.01
Vested			(82,084	)			23.86
Forfeited			(24,000	)			30.87
Outstanding at December 31, 2015			179,026			$	34.92
Granted			141,784				39.73
Vested			(100,330	)			32.47
Forfeited			(9,999	)			40.99
Outstanding at December 31, 2016			210,481			$	39.02
Granted			237,542				37.30
Vested			(165,923	)			37.99
Forfeited			—				—
Outstanding at December 31, 2017			282,100			$	38.06

SARs Activity

The following table summarizes SARs activity during the three year period ended December 31, 2017:

Stock Appreciation Rights		Units				Weighted- Average Exercise Price				Weighted- Average Remaining Contractual Term				Aggregate Intrinsic Value
Outstanding at December 31, 2014			1,060,250			$	29.97
Granted			259,600				43.97
Exercised			(167,500	)			23.90
Forfeited			(102,500	)			27.82
Outstanding at December 31, 2015			1,049,850			$	34.61				5.46			$	13,425
Granted			244,000				40.64
Exercised			(18,750	)			24.28
Forfeited			(30,500	)			28.23
Outstanding at December 31, 2016			1,244,600			$	36.11				4.80			$	3,511
Granted			235,000				38.05
Exercised			(94,250	)			22.21
Forfeited			(193,000	)			32.53
Outstanding at December 31, 2017			1,192,350			$	38.17				4.36			$	2,278
Exercisable at December 31, 2015			153,575			$	38.12				5.59			$	1,425
Exercisable at December 31, 2016			424,992			$	34.49				4.39			$	2,315
Exercisable at December 31, 2017			613,808			$	37.68				3.72			$	1,904

X

- References

No definition available.

+ Details

Name:	us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year.

+ 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)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for stock appreciation rights awards that were outstanding at the beginning and end of the year, and the number of stock appreciation rights awards that were granted, exercised or converted, forfeited, and expired during the year.

+ 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)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ScheduleOfShareBasedCompensationStockAppreciationRightsAwardActivityTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value.

+ 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 (d)
-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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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

+ Details

Name:	us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.

+ 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 (f)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration