Derivative Financial Instruments (Tables)

12 Months Ended

Dec. 31, 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 December 31, 2018 and 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.

	Net Notional
	2018		2017
Foreign exchange contracts:
Swaps	$	929.5	$	515.4
Futures, forwards and spot	3,249.9		3,274.5
Written options	3,688.8		2,934.2
Purchased options	2,867.2		2,314.1
Total	$	10,735.4	$	9,038.2

Schedule of Derivative Liabilities at Fair Value

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

December 31, 2018	Fair Value, Gross				Fair Value, Net
	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Derivatives - undesignated:
Foreign exchange contracts	$	109.5	$	112.9	$	68.8	$	72.1
Cash collateral	9.6		73.1		9.6		73.1
Total net derivative assets and liabilities	$	99.9	$	39.8	$	59.2	$	(1.0	)

December 31, 2017	Fair Value, Gross				Fair Value, Net
	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Derivatives - undesignated:
Over the counter	$	80.4	$	68.2	$	39.0	$	26.8
Exchange traded	—		0.1		—		0.1
Foreign exchange contracts	80.4		68.3		39.0		26.9
Cash collateral	12.5		10.9		12.5		10.9
Total net derivative assets and liabilities	$	67.9	$	57.4	$	26.5	$	16.0

Schedule of Derivative Assets at Fair Value

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

December 31, 2018	Fair Value, Gross				Fair Value, Net
	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Derivatives - undesignated:
Foreign exchange contracts	$	109.5	$	112.9	$	68.8	$	72.1
Cash collateral	9.6		73.1		9.6		73.1
Total net derivative assets and liabilities	$	99.9	$	39.8	$	59.2	$	(1.0	)

December 31, 2017	Fair Value, Gross				Fair Value, Net
	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Derivatives - undesignated:
Over the counter	$	80.4	$	68.2	$	39.0	$	26.8
Exchange traded	—		0.1		—		0.1
Foreign exchange contracts	80.4		68.3		39.0		26.9
Cash collateral	12.5		10.9		12.5		10.9
Total net derivative assets and liabilities	$	67.9	$	57.4	$	26.5	$	16.0