Derivative Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Notional Amounts of Outstanding Derivative Positions

The aggregate equivalent U.S. dollar notional amount of foreign exchange derivative customer contracts held by the Company as of June 30, 2018 and December 31, 2017 (in millions) is presented in the table below. Notional amounts do not reflect the netting of offsetting trades, although these offsetting positions may result in minimal overall market risk. Aggregate derivative notional amounts can fluctuate from period to period in the normal course of business based on market conditions, levels of customer activity and other factors.

	Notional
	June 30, 2018		December 31, 2017
Foreign exchange contracts:
Swaps	$	324.2	$	515.4
Futures, forwards and spot	3,855.9		3,274.5
Written options	3,245.7		2,934.2
Purchased options	2,800.1		2,314.1
Total	$	10,225.9	$	9,038.1

Schedule of Derivative Assets at Fair Value

The following table summarizes the fair value of derivatives reported in the Unaudited Consolidated Balance Sheet as of June 30, 2018 and December 31, 2017 (in millions):

	June 30, 2018								December 31, 2017
	Fair Value, Gross				Fair Value, Net				Fair Value, Gross				Fair Value, Net
	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Derivatives - undesignated:
Over the counter	$	88.8	$	86.8	$	43.0	$	41.0	$	80.4	$	68.2	$	39.0	$	26.8
Exchange traded	—		—		—		—		—		0.1		—		0.1
Foreign exchange contracts	88.8		86.8		43.0		41.0		80.4		68.3		39.0		26.9
Cash collateral	40.1		9.9		40.1		9.9		12.5		10.9		12.5		10.9
Total net derivative assets and liabilities	$	48.7	$	76.9	$	2.9	$	31.1	$	67.9	$	57.4	$	26.5	$	16.0

Schedule of Derivative Liabilities at Fair Value

The following table summarizes the fair value of derivatives reported in the Unaudited Consolidated Balance Sheet as of June 30, 2018 and December 31, 2017 (in millions):

	June 30, 2018								December 31, 2017
	Fair Value, Gross				Fair Value, Net				Fair Value, Gross				Fair Value, Net
	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Derivatives - undesignated:
Over the counter	$	88.8	$	86.8	$	43.0	$	41.0	$	80.4	$	68.2	$	39.0	$	26.8
Exchange traded	—		—		—		—		—		0.1		—		0.1
Foreign exchange contracts	88.8		86.8		43.0		41.0		80.4		68.3		39.0		26.9
Cash collateral	40.1		9.9		40.1		9.9		12.5		10.9		12.5		10.9
Total net derivative assets and liabilities	$	48.7	$	76.9	$	2.9	$	31.1	$	67.9	$	57.4	$	26.5	$	16.0