Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Expense, Amount

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Number of Simulations

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Other than Options, Vested and Expected to Vest, Range Based on Return on Average Assets (ROAA)

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Other than Options, Vested and Expected to Vest, Range Based on Shareholder Return

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Taxes Paid for Vesting of Employee Share Units

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No definition available.

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- Definition

Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

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No definition available.

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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

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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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- Definition

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

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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

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).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, 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.

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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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No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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No definition available.

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Weighted average remaining contractual term for option awards outstanding, 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 options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Share-based Compensation (Narrative) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) simulation $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Apr. 25, 2013 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 14,200	$ 13,600	$ 12,600
Tax benefit recognized from compensation expense	5,200	5,000	4,600
Unrecognized compensation cost	17,500
Options outstanding, aggregate intrinsic value	$ 23,800
Options outstanding, weighted average remaining contractual term (years)	4 years 2 months 5 days
Options exercised, intrinsic value	$ 5,100	4,700	4,400
Cash received from option exercises	$ 3,440	5,155	5,643
Total grant date fair value of stock options vested		$ 7,400	$ 6,500
Options expired/canceled (in shares) \| shares	0	469,792	456,438
Options expired (in dollars per share) \| $ / shares	$ 0.00	$ 92.62	$ 94.56
Share-based compensation, excess tax expense, amount	$ 1,700
Share-based compensation tax benefit (deficiency)	5,000	$ (790)	$ 1,656
Contractual Expiration Dates in 2017 and 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options expired/canceled (in shares) \| shares		317,524
Options expired (in dollars per share) \| $ / shares		$ 93.62
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from option exercises	$ 3,400	$ 5,200	$ 5,600
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Non-option awards granted (in shares) \| shares	242,804	350,458	321,874
Non-option awards granted, weighted-average grant-date fair value (in dollars per share) \| $ / shares	$ 41.82	$ 26.43	$ 28.09
Unrecognized compensation cost	$ 9,900
Non-option awards vested, total fair value	$ 14,400	$ 11,400	$ 12,300
Unrecognized compensation cost, period of recognition (years)	1 year 5 months 5 days
Taxes paid for vesting of employee share units	$ 8,000	$ 5,000	$ 5,100
Market Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Non-option awards granted (in shares) \| shares	78,174	93,913	82,152
Non-option awards granted, weighted-average grant-date fair value (in dollars per share) \| $ / shares	$ 43.52	$ 26.93	$ 29.39
Unrecognized compensation cost	$ 3,500
Number of simulations \| simulation	100,000
Non-option awards vested, total fair value	$ 4,800	$ 2,600	$ 1,400
Unrecognized compensation cost, period of recognition (years)	1 year 5 months 16 days
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-option awards granted (in shares) \| shares	72,825	83,529	82,152
Non-option awards granted, weighted-average grant-date fair value (in dollars per share) \| $ / shares	$ 41.61	$ 25.95	$ 28.06
Unrecognized compensation cost	$ 4,100
Non-option awards vested, total fair value	$ 2,900
Unrecognized compensation cost, period of recognition (years)	1 year 5 months 9 days
Minimum \| Market Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting range based on return on average assets (ROAA)	75.00%
Minimum \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, vested and expected to vest, range based on return on average assets	0.00%
Maximum \| Market Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting range based on return on average assets (ROAA)	125.00%
Maximum \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, vested and expected to vest, range based on return on average assets	150.00%
2013 Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of authorized but unissued common stock reserved for future grants (in shares) \| shares	5,700,000			8,600,000
2013 Omnibus Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
2013 Omnibus Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Contractual terms	10 years