Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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Face (par) amount of debt instrument at time of issuance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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Contractual interest rate for funds borrowed, under the debt agreement.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
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-Number 210
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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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Debt (Parenthetical) (Detail) - USD ($)	12 Months Ended
Debt (Parenthetical) (Detail) - USD ($)	Dec. 31, 2015	Jan. 26, 2015	Dec. 31, 2014	Apr. 25, 2014	Jun. 18, 2007
Debt Instrument [Line Items]
Senior notes, issuance amount		$ 400,000,000		$ 350,000,000
Debt instrument, outstanding	$ 2,729,300,000
Debt Instrument, Interest Rate, Stated Percentage		3.70%		4.35%
3.75% Senior Notes due 2021
Debt Instrument [Line Items]
Senior notes, issuance amount	$ 500,000,000		$ 500,000,000
Debt Instrument, Interest Rate, Stated Percentage	3.75%
6 5/8% Senior Notes due 2029
Debt Instrument [Line Items]
Senior notes, issuance amount	$ 300,000,000		300,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.625%
6.25% Senior Notes due 2032
Debt Instrument [Line Items]
Senior notes, issuance amount	$ 400,000,000		400,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.25%
4.35% Senior Notes due 2044
Debt Instrument [Line Items]
Senior notes, issuance amount	$ 350,000,000		350,000,000	$ 350,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.35%			4.35%
3.70% Senior Notes due 2045
Debt Instrument [Line Items]
Senior notes, issuance amount	$ 400,000,000	$ 400,000,000	0
Debt Instrument, Interest Rate, Stated Percentage	3.70%	3.70%			6.70%
6.70% Fixed-to-Floating Rate Junior Subordinated Debentures due 2067
Debt Instrument [Line Items]
Senior notes, issuance amount	$ 1,000,000,000		1,000,000,000
Debt instrument, outstanding	$ 614,300,000		$ 632,800,000
Debt Instrument, Interest Rate, Stated Percentage	6.70%
Discretionary Line of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate Description	advances under the Line of Credit (if any) will bear interest at a variable rate equal to the higher of PNC's Prime Rate or the sum of the Federal Funds Open Rate plus 50 basis points.
Long-term Line of Credit	$ 0