Income Taxes - Schedule of Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income tax at U.S. federal statutory tax rate	35.00%	35.00%	35.00%
Effective income tax rate reconciliation, Impact of the Tax Act	32.20%
State taxes, net of federal benefit	2.20%	1.90%	1.90%
Low-income housing, new markets tax credits, and other credits	(5.80%)	(4.90%)	(4.00%)
Other foreign tax differences, net	(1.50%)	(1.40%)	(1.30%)
Other, net	(0.60%)	0.70%	0.20%
Effective tax rate	61.50%	31.30%	31.80%