Deposits (Summary Of Deposits) (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Deposits [Abstract]
Non-interest bearing	$ 2,622,518	$ 2,396,264	$ 2,162,215
NOW	1,922,906	2,022,957	1,841,743
Wealth management deposits	1,099,509	991,902	979,306
Money market	3,423,413	2,761,498	2,596,702
Savings	1,318,147	1,275,012	1,156,466
Time certificates of deposit	4,260,953	4,980,911	5,111,533
Total deposits	$ 14,647,446	$ 14,428,544	$ 13,847,965
Non-interest bearing, Mix	18.00%	17.00%	16.00%
NOW, Mix	13.00%	14.00%	13.00%
Wealth management deposits, Mix	8.00%	7.00%	7.00%
Money market, Mix	23.00%	19.00%	19.00%
Savings, Mix	9.00%	9.00%	8.00%
Time certificates of deposit, Mix	29.00%	34.00%	37.00%
Total deposits, Mix	100.00%	100.00%	100.00%

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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 210.9-03.12)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 9

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- Definition

Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

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Amount of deposits in interest-bearing transaction accounts at banks or savings and loans, that are restricted in regard to ownership and can usually only be held by individuals, nonprofit entities and governments. Negotiable order of withdrawal accounts differ from money market demand accounts as they typically have higher reserve requirements and no limit on the number of checks that can be written.

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Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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Percentage of interest-bearing domestic money market demand account deposit liabilities to total deposit liabilities.

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Percentage of interest-bearing domestic savings deposit liabilities to total deposit liabilities.

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Percentage of interest-bearing domestic time deposit liabilities to total deposit liabilities.

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Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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Deposits negotiable order of withdrawal NOW, percentage

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Deposits, Percentage

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Non-interest bearing, percentage

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Wealth management deposits

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Wealth management deposits, percentage

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