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Debt Commitments and Contingencies - Additional Information (Details) - USD ($)	1 Months Ended	6 Months Ended
	Dec. 31, 2015	Jun. 30, 2016	Dec. 07, 2015
Debt Instrument [Line Items]
Debt	$ 365,000,000	$ 430,000,000
Apex Industrial Technologies, LLC [Member]
Debt Instrument [Line Items]
Consideration for assets and transition arrangement			$ 27,000,000
Cash paid for assets and transition arrangement	12,000,000
Credit Facility [Member]
Debt Instrument [Line Items]
Weighted per annum interest rate on outstanding line of credit		1.40%
Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Percentage fee paid for undrawn portion of credit facility		0.10%
Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Percentage fee paid for undrawn portion of credit facility		0.125%
Credit Facility [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Per annum interest rate over LIBOR		0.95%
Credit Facility [Member] \| Unsecured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		$ 700,000,000
Debt	350,000,000	415,000,000
Credit Facility [Member] \| Letter of Credit Subfacility [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		55,000,000
Note Payable [Member]
Debt Instrument [Line Items]
Debt	$ 15,000,000	$ 15,000,000
Annual interest rate		0.56%