Amount of equity securities categorized neither as held-to-maturity nor as trading.

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Investment Securities - Gains and (Losses) Recognized in Earnings (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) security	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) security	Sep. 30, 2017 USD ($)	Jan. 01, 2018 USD ($)	Dec. 31, 2017 USD ($)
Investments, Debt and Equity Securities [Abstract]
Securities in unrealized loss positions, qualitative disclosure, number of positions (in security) \| security	1,525		1,525
Proceeds	$ 0	$ 7,035	$ 4,215	$ 17,085
Gross gains	0	1	42	168
Gross losses	0	$ 0	(39)	$ 0
Schedule of Investments [Line Items]
Fair Value						$ 1,824
Adjustments to retained earnings	$ 567,510		$ 567,510			419,403
ASU 2016-01
Schedule of Investments [Line Items]
Adjustments to retained earnings					$ (344)	(300)
Preferred stock
Schedule of Investments [Line Items]
Fair Value					$ 1,800	$ 1,824