Pension and Employee Benefit Plans - Details of Defined Benefit Pension Plan Asset Allocation by Asset Category (Detail) |
12 Months Ended | |
---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
|
Defined Benefit Plan Disclosure [Line Items] | ||
Target Allocation | 100.00% | |
Percentage of Plan Assets | 100.00% | 100.00% |
Cash and cash equivalents [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Target Allocation | 0.00% | |
Percentage of Plan Assets | 4.00% | 25.00% |
Equity Securities [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Target Allocation | 70.00% | |
Percentage of Plan Assets | 67.00% | 52.00% |
Debt Securities [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Target Allocation | 30.00% | |
Percentage of Plan Assets | 29.00% | 23.00% |