Deposits (Balances for Core Deposits and Time Deposits) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Core Deposits
Noninterest-bearing demand	$ 11,080,036	$ 11,377,009
Interest-bearing checking	5,200,755	4,584,447
Money market	8,711,964	8,262,677
Savings	2,117,196	2,146,429
Time deposits:
Less than $100,000	1,993,950	1,957,121
$100,000 or greater	8,220,358	7,111,945
Total deposits	37,324,259	35,439,628
Time deposits	10,214,308
Hong Kong and China
Time deposits:
Interest-bearing demand deposit	493,400	621,300
Time deposits	1,210,000	1,210,000
Geographic Distribution, Domestic \| United States
Time deposits:
Time deposits, at or above FDIC insurance limit	5,440,000	4,450,000
Geographic Distribution, Foreign \| Hong Kong and China
Time deposits:
Time deposits, at or above FDIC insurance limit	$ 1,190,000	$ 1,190,000

Core Deposits [Abstract]

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Core Deposits [Line Items]

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Amount of interest-bearing checking deposit liabilities.

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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.

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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 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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Amount of money in interest-bearing foreign accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits. Checking and negotiable order withdrawals (NOW) are the most common forms of demand deposits.

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

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Amount of time deposit liabilities, including certificates of deposit.

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Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

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

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