Discount in percentage terms at which long term debt was issued.

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- Definition

Long-Term Debt Qualifying as Risk Based Capital

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No definition available.

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- Definition

Outstanding Bank Notes Offering Capacity

+ References

No definition available.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Amount of long-term debt classified as other.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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Summary of Long-Term Debt Outstanding (Detail) - USD ($)		12 Months Ended
	Nov. 06, 2013	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Capital Lease Obligations		$ 23,000,000	$ 29,700,000
Total Long-Term Debt		1,330,900,000	1,371,300,000
Long-Term Debt Qualifying as Risk-Based Capital		809,300,000	909,200,000
Debt issue costs			2,600,000
Increases in the carrying values of notes outstanding covered by interest-rate swap contracts		$ 0	0	$ 0
Fixed Rate Due Aug. 2022
Debt Instrument [Line Items]
Interest Rate		2.38%
Notes issued at a discount		0.283%
5.85% Notes due Nov. 2017
Debt Instrument [Line Items]
Interest Rate		5.85%
Long Term Debt		$ 207,600,000	214,500,000
6.50% Notes due Aug. 2018
Debt Instrument [Line Items]
Interest Rate		6.50%
Long Term Debt		$ 315,300,000	326,700,000
Notes issued at a discount		0.02%
6.50% Notes due Aug. 2018 \| Upper Limit
Debt Instrument [Line Items]
Debt maturity	15 years
6.50% Notes due Aug. 2018 \| Lower Limit
Debt Instrument [Line Items]
Debt maturity	5 years
Bank Subordinated Debt
Debt Instrument [Line Items]
Long Term Debt		$ 522,900,000	541,200,000
Corporation-Subordinated 3.95% Notes due Oct. 2025
Debt Instrument [Line Items]
Interest Rate		3.95%
Long Term Debt		$ 785,000,000	800,400,000
Notes issued at a discount		0.114%
Senior Notes
Debt Instrument [Line Items]
Offering Circular, ability to offer notes in aggregate principal amount	$ 4,500,000,000.0
Debt issue costs		$ 1,100,000
Senior Notes \| Upper Limit
Debt Instrument [Line Items]
Debt maturity	15 years
Senior Notes \| Lower Limit
Debt Instrument [Line Items]
Debt maturity	30 days
Subordinated Debt
Debt Instrument [Line Items]
Offering Circular, ability to offer notes in aggregate principal amount	$ 1,000,000,000
Subordinated Debt \| Interest Rate Swaps
Debt Instrument [Line Items]
Increases in the carrying values of notes outstanding covered by interest-rate swap contracts		59,600,000	$ 92,400,000
Long Term Debt
Debt Instrument [Line Items]
Debt issue costs		$ 1,000,000
Fixed Rate Due Nov. 2020
Debt Instrument [Line Items]
Interest Rate		3.45%
Notes issued at a discount		0.117%
Fixed Rate Due Aug. 2021
Debt Instrument [Line Items]
Interest Rate		3.38%
Notes issued at a discount		0.437%