Deposits - Interest Bearing Deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Interest-bearing Deposit Liabilities, Domestic, by Component [Abstract]
Money market	$ 7,129,404	$ 4,886,299
Savings	834,521	669,254
Certificates of deposit	5,471,065	5,931,453
Deposits - interest bearing	$ 13,434,990	$ 11,487,006
Year-End Weighted Average Stated Rate
Money market	1.22%	1.19%
Savings	0.84%	0.82%
Certificates of deposit	1.41%	0.98%

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

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 interest-bearing domestic money market demand account deposit liabilities.

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Amount of interest-bearing domestic savings deposit liabilities. Saving deposits bear interest and have no stated maturity.

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Amount of interest-bearing domestic time deposits. Time deposits bear interest for a fixed, stated period of time and include certificate of deposits and individual retirement accounts.

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The weighted average interest rate for domestic money market demand account deposit liabilities.

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The weighted average interest rate for domestic savings deposit liabilities.

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The weighted average interest rate for domestic time deposit liabilities.

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