Employee Benefit Plans - Summary of Pension Plan Assets (Detail) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		$ 50,959	$ 54,155
Investments in equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		24,693	28,390
Investments in equity securities | Us Large Cap Equity Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	7,671	8,097
Investments in equity securities | Us Mid Cap Equity Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	3,186	3,447
Investments in equity securities | United States Equity Small Cap
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	1,683	1,694
Investments in equity securities | International All Cap Equity
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[2]	9,416	9,621
Investments in equity securities | Alternative Strategies
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[3]	2,737	5,531
Debt securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		21,086	20,375
Debt securities | Fixed Income
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[4]	18,565	17,717
Debt securities | High Yield Asset Backed Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[4]	2,521	2,658
Other
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		5,180	5,390
Other | Commodities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[5]	1,365	1,819
Other | Real Estate
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[6]	2,529	2,427
Other | Guaranteed deposit
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[7]	1,286	1,144
Quoted Prices in Active Markets (Level 1)
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		43,216	46,448
Quoted Prices in Active Markets (Level 1) | Investments in equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		18,236	21,827
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | Us Large Cap Equity Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	3,641	4,069
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | Us Mid Cap Equity Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	1,577	1,733
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | United States Equity Small Cap
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	865	873
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | International All Cap Equity
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[2]	9,416	9,621
Quoted Prices in Active Markets (Level 1) | Investments in equity securities | Alternative Strategies
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[3]	2,737	5,531
Quoted Prices in Active Markets (Level 1) | Debt securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		21,086	20,375
Quoted Prices in Active Markets (Level 1) | Debt securities | Fixed Income
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[4]	18,565	17,717
Quoted Prices in Active Markets (Level 1) | Debt securities | High Yield Asset Backed Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[4]	2,521	2,658
Quoted Prices in Active Markets (Level 1) | Other
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		3,894	4,246
Quoted Prices in Active Markets (Level 1) | Other | Commodities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[5]	1,365	1,819
Quoted Prices in Active Markets (Level 1) | Other | Real Estate
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[6]	2,529	2,427
Quoted Prices in Active Markets (Level 1) | Other | Guaranteed deposit
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[7]	0	0
Significant Other Observable Inputs (Level 2)
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		6,457	6,563
Significant Other Observable Inputs (Level 2) | Investments in equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		6,457	6,563
Significant Other Observable Inputs (Level 2) | Investments in equity securities | Us Large Cap Equity Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	4,030	4,028
Significant Other Observable Inputs (Level 2) | Investments in equity securities | Us Mid Cap Equity Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	1,609	1,714
Significant Other Observable Inputs (Level 2) | Investments in equity securities | United States Equity Small Cap
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	818	821
Significant Other Observable Inputs (Level 2) | Investments in equity securities | International All Cap Equity
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[2]	0	0
Significant Other Observable Inputs (Level 2) | Investments in equity securities | Alternative Strategies
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[3]	0	0
Significant Other Observable Inputs (Level 2) | Debt securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		0	0
Significant Other Observable Inputs (Level 2) | Debt securities | Fixed Income
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[4]	0	0
Significant Other Observable Inputs (Level 2) | Debt securities | High Yield Asset Backed Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[4]	0	0
Significant Other Observable Inputs (Level 2) | Other
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		0	0
Significant Other Observable Inputs (Level 2) | Other | Commodities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[5]	0	0
Significant Other Observable Inputs (Level 2) | Other | Real Estate
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[6]	0	0
Significant Other Observable Inputs (Level 2) | Other | Guaranteed deposit
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[7]	0	0
Significant Unobservable Inputs (Level 3)
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		1,286	1,144	$ 602
Significant Unobservable Inputs (Level 3) | Investments in equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | Us Large Cap Equity Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | Us Mid Cap Equity Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | United States Equity Small Cap
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[1]	0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | International All Cap Equity
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[2]	0	0
Significant Unobservable Inputs (Level 3) | Investments in equity securities | Alternative Strategies
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[3]	0	0
Significant Unobservable Inputs (Level 3) | Debt securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		0	0
Significant Unobservable Inputs (Level 3) | Debt securities | Fixed Income
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[4]	0	0
Significant Unobservable Inputs (Level 3) | Debt securities | High Yield Asset Backed Securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[4]	0	0
Significant Unobservable Inputs (Level 3) | Other
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets		1,286	1,144
Significant Unobservable Inputs (Level 3) | Other | Commodities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[5]	0	0
Significant Unobservable Inputs (Level 3) | Other | Real Estate
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[6]	0	0
Significant Unobservable Inputs (Level 3) | Other | Guaranteed deposit
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total Pension Plan Assets	[7]	$ 1,286	$ 1,144

[1] Includes funds that invest primarily in United States common stocks.

[2] Includes funds that invest primarily in foreign equities and emerging markets equities.

[3] Includes funds that actively invest in both equity and debt securities, funds that sell short securities and funds that provide long-term capital appreciation. The funds may invest in debt securities below investment grade.

[4] Includes funds that invest in investment grade and fixed income securities.

[5] Includes funds that invest primarily in commodity-linked derivative instruments and fixed income securities.

[6] Includes funds that invest primarily in real estate.

[7] Includes investment in a group annuity product issued by an insurance company.