Short-Term Borrowings

Short-term borrowings include federal funds purchased and securities sold under agreements to repurchase, trading liabilities, and other borrowed funds.

Federal funds purchased and securities sold under agreements to repurchase generally have maturities of less than 90 days. Trading liabilities, which represent short positions in securities, are generally held for less than 90 days. Other short-term borrowings have original maturities of one year or less. On December 31, 2017, fixed income trading securities with a fair value of $68.9 million were pledged to secure other short-term borrowings.

The detail of short-term borrowings for the years 2017, 2016 and 2015 is presented in the following table:



(Dollars in thousands)	Federal Funds Purchased			Securities Sold Under Agreements to Repurchase			Trading Liabilities			Other Short-term Borrowings
2017
Average balance	$	447,137		$	578,666		$	685,891		$	554,502
Year-end balance	399,820			656,602			638,515			2,626,213
Maximum month-end outstanding	568,490			743,684			896,943			2,626,213
Average rate for the year	1.06		%	0.72		%	2.26		%	1.28		%
Average rate at year-end	1.48			0.64			2.22			1.44
2016
Average balance	$	589,223		$	425,452		$	771,039		$	198,440
Year-end balance	414,207			453,053			561,848			83,177
Maximum month-end outstanding	695,083			528,024			874,076			792,736
Average rate for the year	0.52		%	0.08		%	1.95		%	0.67		%
Average rate at year-end	0.73			0.08			2.46			0.96
2015
Average balance	$	705,054		$	370,097		$	733,189		$	164,951
Year-end balance	464,166			338,133			566,019			137,861
Maximum month-end outstanding	1,228,125			524,191			866,005			339,468
Average rate for the year	0.26		%	0.06		%	2.18		%	0.67		%
Average rate at year-end	0.50			0.09			2.41			0.82