Deferred Compensation Awards - Schedule of Recipients of Awards, Grant Date, Units Granted, Exercise Price, Outstanding Shares and Amounts Paid (Parenthetical) (Details) - Stock Appreciation Rights (SARs)	12 Months Ended
	Dec. 31, 2016
Employees below senior management level | Q1 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting terms	The SARs vested in equal installments over four quarters
Expiration period	4 years
Key Executive | Q3 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting terms	The SARs vest ratably over sixteen quarters from the grant date
Key Executive | Q4 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting terms	The SARs vest ratably over sixteen quarters from the grant date
Key Executive | Q2 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting terms	The SARs vest over sixteen quarters, vesting 20% per year for the first three years, with the remainder (40%) vesting in year four.
Key Executive | Q2 2015 | First Three Years
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage	20.00%
Key Executive | Q2 2015 | Year Four
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage	40.00%
Members of Management | Q1 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting terms	The SARs vest ratably over sixteen quarters from the grant date