Deposits (Summary Of Deposits) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Banking and Thrift [Abstract]
Demand	$ 4,191,496	$ 4,021,061
Checking	2,736,952	2,528,274
Health Savings Accounts	5,038,681	4,362,503
Money market	2,209,492	2,047,121
Savings	4,348,700	4,320,090
Time deposits	2,468,408	2,024,808
Total interest-bearing	16,802,233	15,282,796
Total deposits	20,993,729	19,303,857
Time deposits and interest-bearing checking, included in above balances, obtained through brokers	898,157	848,618
Time deposits, included in above balance, that meet or exceed the FDIC limit	561,512	490,721
Demand deposit overdrafts reclassified as loan balances	$ 2,210	$ 1,885

No definition available.

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- Definition

Amount of deposits held by the entity that have been reclassified as loan balances receivable, for example, but not limited to, overdrafts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

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- Definition

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.

+ References

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

+ Details

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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.

+ References

+ Details

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- Definition

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

+ References

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- Definition

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

+ References

+ Details

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- Definition

Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

+ References

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- Definition

Amount of interest-bearing domestic checking deposit liabilities.

+ References

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- Definition

Amount of other interest-bearing domestic deposit liabilities.

+ References

No definition available.

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- Definition

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

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- Definition

Amount of time deposit liabilities, including certificates of deposit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

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