Property, Equipment and Capitalized Software - Useful Life (Details)	12 Months Ended
	Dec. 31, 2017
Minimum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	1 year
Maximum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	30 years
Buildings [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	30 years
Equipment [Member] | Minimum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	2 years
Equipment [Member] | Maximum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	5 years
Furniture [Member] | Minimum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	5 years
Furniture [Member] | Maximum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	10 years
Capitalized Software [Member] | Minimum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	2 years
Capitalized Software [Member] | Maximum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	5 years
Other Software [Member] | Minimum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	1 year
Other Software [Member] | Maximum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	5 years
Leasehold Improvements [Member] | Minimum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	3 years
Leasehold Improvements [Member] | Maximum [Member]
Property, Equipment and Capitalized Software [Line Items]
Property, equipment and capitalized software, useful life	10 years