Annual equity awards granted non employee directors.

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Duration of performance evaluation for stock units to vest.

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Period (in years) from the grant date in which stock options expire.

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Percentage of performance conditions achieved.

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- Definition

Quarterly value of shares available for purchase under dividend reinvestment and stock purchase plan.

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- Definition

Restriction lapsing rate for grant of restricted stock to nonemployee directors.

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- Definition

Value of annual equity awards to non employee directors.

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No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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-Name Accounting Standards Codification
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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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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.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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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.

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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.

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

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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-Name Accounting Standards Codification
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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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Stock Options, Restricted Stock Incentive, And Dividend Revinvestment Plans (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for grants	7,326,277
Compensation cost included in income from continuing operations for stock option and restricted stock plans	$ 13,796,000	$ 11,351,000	$ 16,144,000
Total income tax benefits recognized in income statements	$ 5,300,000	$ 4,400,000	$ 6,200,000
Stock options granted	595,229	592,551	866,742
Weighted average fair value of stock option at grant date	$ 4.01	$ 3.5	$ 3.21
Duration of performance evaluation	3 years
Performance Condition Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting Period	3 years
Duration of performance evaluation	3 years	3 years	3 years
Market Condition Award [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting Period	5 years
Stock Option Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted expiration	P7Y
Vesting Period	4 years
Intrinsic value of options exercised	$ 2,800,000	$ 400,000
Parent Company [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation cost included in income from continuing operations for stock option and restricted stock plans	$ 13,796,000	11,351,000	$ 16,144,000
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for grants	7,326,277
Total grant date fair value of shares vested	$ 9,900,000	15,500,000	$ 13,800,000
Restricted Stock [Member] \| Director Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares granted to non-employee director, prior to 2007	8930
Employee Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost of nonvested restricted stock plans and stock options	$ 1,400,000
Recognizable weighted-average period of unrecognized compensation cost	2 years 7 months
Restricted Stock Units RSU [Member] \| Director Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restriction lapsing rate for grants of restricted stock, awarded prior to 2007, to non-employee directors	10.00%
Value of annual equity awards to non-employee directors	$ 65,000	$ 45,000
Stock Options Included In Deferral Program Granted Prior To January Two Two Thousand Four [Member] \| Stock Option Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted expiration	P20Y
Stock Options Included In Deferral Program Granted After January Two Two Thousand Four [Member] \| Stock Option Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted expiration	P10Y
Nonvested Restricted Stock Plans [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost of nonvested restricted stock plans and stock options	$ 22,000,000
Recognizable weighted-average period of unrecognized compensation cost	2 years 10 months
2012 Units \| Performance Condition Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of performance conditions achieved	87.50%
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Quarterly value of shares available for purchase under dividend reinvestment and stock purchase plan	$ 10,000
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Quarterly value of shares available for purchase under dividend reinvestment and stock purchase plan	$ 25