Bank Deposits (Schedule Of Deposits) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deposits Liabilities Balance Sheet Reported Amounts [Abstract]
Money market and savings accounts	$ 6,429,780	$ 4,600,757
Demand deposits (interest-bearing)	185,275	101,652
Certificates of deposit	15,087	77,197
Demand deposits (non-interest-bearing)	8,214	10,475
Bank deposits	$ 6,638,356	$ 4,790,081
Weighted average interest rate on deposits	0.17%	0.19%

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

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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

Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

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- Definition

Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

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- Definition

Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required.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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- Definition

The weighted average interest rate for domestic time deposit liabilities.

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