Deposits (Balances for Core Deposits and Time Deposits) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Time Deposits
Less than $100,000	$ 1,176,973	$ 1,300,091
$100,000 or greater	4,463,776	4,315,178
Total time deposits	5,640,749	5,615,269
Total deposits	31,615,063	29,890,983
Core deposits:
Noninterest-bearing demand	10,887,306	10,183,946
Interest-bearing checking	4,419,089	3,674,417
Money market	8,359,425	8,174,854
Savings	2,308,494	2,242,497
Total core deposits	25,974,314	24,275,714
Geographic Distribution, Foreign \| Hong Kong and China
Time Deposits
Time Deposits, at or Above FDIC Insurance Limit	814,600	538,000
Geographic Distribution, Foreign \| China
Time Deposits
$100,000 or greater	507,100	329,900
Geographic Distribution, Foreign \| Hong Kong
Time Deposits
$100,000 or greater	322,000	219,700
Geographic Distribution, Domestic \| UNITED STATES
Time Deposits
Time Deposits, at or Above FDIC Insurance Limit	$ 2,370,000	$ 2,350,000

The aggregate of all deposit liabilities held by the entity excluding time deposits.

No definition available.

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- Definition

Core Deposits [Abstract]

+ References

No definition available.

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- Definition

Amount of interest-bearing checking deposit liabilities.

+ References

No definition available.

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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

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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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- Definition

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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- 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 of $100,000 or more.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
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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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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of less than $100,000.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
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