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Debt Commitments and Contingencies - Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Cash paid for acquisition		$ 23,493,000	$ 5,575,000	$ 0
Debt	$ 365,000,000	365,000,000	90,000,000
Apex Industrial Technologies, LLC [Member]
Debt Instrument [Line Items]
Consideration for assets and transition arrangement	27,000,000	$ 27,000,000
Cash paid for acquisition	$ 12,000,000
Credit Facility [Member]
Debt Instrument [Line Items]
Weighted per annum interest rate on outstanding line of credit	1.40%	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]
Interest percentage over LIBOR rate		0.95%
Credit Facility [Member] \| Unsecured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 700,000,000	$ 700,000,000
Debt	350,000,000	350,000,000	90,000,000
Credit Facility [Member] \| Letter of Credit Subfacility [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	55,000,000	55,000,000
Note [Member]
Debt Instrument [Line Items]
Debt	$ 15,000,000	$ 15,000,000	$ 0
Interest rate	0.56%	0.56%