Shareholders' Equity (Tables)

3 Months Ended

Mar. 31, 2017

Stockholders' Equity Note [Abstract]

Accumulated Other Comprehensive Income (Loss) [Table Text Block]

A rollforward of the components of accumulated other comprehensive income (loss) is included as follows (in thousands):

	Unrealized Gain (Loss) on
	Available for Sale Securities			Investment Securities Transferred from AFS			Employee Benefit Plans			Total
Balance, Dec. 31, 2015	$	23,284		$	68		$	(1,765	)	$	21,587
Net change in unrealized gain (loss)	121,091			—			—			121,091
Reclassification adjustments included in earnings:
Interest revenue, Investment securities, Taxable securities	—			(69		)	—			(69		)
Gain on available for sale securities, net	(3,964		)	—			—			(3,964		)
Other comprehensive income (loss), before income taxes	117,127			(69		)	—			117,058
Federal and state income taxes1	45,563			(27		)	—			45,536
Other comprehensive income (loss), net of income taxes	71,564			(42		)	—			71,522
Balance, March 31, 2016	$	94,848		$	26		$	(1,765	)	$	93,109
Balance, Dec. 31, 2016	$	(9,087	)	$	—		$	(1,880	)	$	(10,967	)
Net change in unrealized gain (loss)	11,411			—			—			11,411
Reclassification adjustments included in earnings:
Interest revenue, Investment securities, Taxable securities	—						—			—
Gain on available for sale securities, net	(2,049		)	—			—			(2,049		)
Other comprehensive income (loss), before income taxes	9,362			—			—			9,362
Federal and state income taxes1	3,616						—			3,616
Other comprehensive income (loss), net of income taxes	5,746			—			—			5,746
Balance, March 31, 2017	$	(3,341	)	$	—		$	(1,880	)	$	(5,221	)

¹  Calculated using a 39 percent effective tax rate.