Defined Benefit Plan, Target Allocation Variance

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- Definition

Defined Contribution Plan, Employer Matching Contribution, Additional Percent of Employees' Gross Pay If Employed at Year End

+ References

No definition available.

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- Definition

Defined Contribution Plan, Employer Matching Contribution, Profit Sharing, Percent of Employees' Gross Pay

+ References

No definition available.

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accumulated Benefit Obligation
-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

The interest rate used to adjust for the time value of money.

+ References

+ Details

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

+ Details

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

+ Details

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- Definition

The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(10)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Curtailment
-URI http://asc.fasb.org/extlink&oid=6520938

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 15
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927

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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

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

No definition available.

+ Details

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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2007
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Allocation Variance		10.00%
Defined Contribution Plan, Cost Recognized			$ 16,400	$ 14,900
Employer contributions		$ 30,000
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage		100.00%
BancShares Plan
Defined Benefit Plan Disclosure [Line Items]
Actual % of Plan Assets	100.00%	100.00%	100.00%
Defined Benefit Plan, Accumulated Benefit Obligation	$ 536,956	$ 533,125	$ 536,956
Employer contributions		$ 30,000	$ 0
Assumed discount rate (percent)		4.27%	4.90%	4.00%
Assumed rate of salary increases		4.00%	4.00%	4.00%
Expected long-term rate of return on plan assets (percent)		7.50%	7.50%	7.25%
Bancorporation Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Curtailments		$ 2,076	$ 0
Defined Benefit Plan, Accumulated Benefit Obligation	$ 136,425	$ 131,879	$ 136,425
Assumed discount rate (percent)		4.27%	4.35%
Assumed rate of salary increases		4.00%	4.00%
Expected long-term rate of return on plan assets (percent)		7.50%	7.50%
Bancorporation Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized			$ 1,100
Percent of employer match	100.00%
Percentage of employee compensation matched	6.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage		100.00%
Employee profit sharing contribution percentage	3.00%
BancShares Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized		$ 22,600
Percent of employer match		75.00%			100.00%
Percentage of employee compensation matched		6.00%			6.00%
Additional contribution if employed at end of year					3.00%
401(k) Matching Range 2 \| Bancorporation Plan
Defined Benefit Plan Disclosure [Line Items]
Percent of employer match	50.00%
Percentage of employee compensation matched	3.00%
401(k) Matching Range 1 \| Bancorporation Plan
Defined Benefit Plan Disclosure [Line Items]
Percent of employer match	100.00%
Percentage of employee compensation matched	3.00%